The Suffering Messiah was prophesied about in the Old Testament.
Here is just one example:
“But He was wounded for our transgressions. He was bruised for our iniquities. The chastisement for our peace was upon Him and by His stripes we are healed.” (Isaiah 53:5)
It was fulfilled here:
“Then he released Barabbas to them. And when he had scourged Jesus, he delivered Him to be crucified.” (Matthew 27:26)
Here is another example:
“I gave My back to those who struck Me and My cheeks to those who plucked out the beard. I did not hide My face from shame and spitting. (Isaiah 50:6)
It was fulfilled here:
“Then they spat in His face and beat Him. And others struck Him with the palms of their hands." (Matthew 26:6)
Regarding Isaiah 53, going back to Isaiah 53:2, it says:
"He grew up before him like a tender shoot, and like a root out of dry ground. He had no beauty or majesty to attract us to him, nothing in his appearance that we should desire him."
That is talking about the Messiah.
Isaiah 49:3, 'servant' cannot mean literally national Israel, since in verse 5 this "servant" has a mission to Israel. The Messianic servant is the ideal Israel through whom the Lord will be glorified. I was going to type more, but since you keep entering comments, you make me feel rushed, so I'm not going to spend much more time here now. There are many verses dealing with this subject in general, and it would take a good bit of time to try to cover it all, but I have a lot of things to do, so I need to be going.
In Isaiah 4:2, it talks about the "Branch of the Lord." This is a Messianic title related to the "shoot" (53:2) and "Branch" descended from David.
"A shoot will come up from the stump of Jesse; from his roots a Branch will bear fruit." (Isaiah 11:1)
In the next verse of Isaiah 53, it says this:
"He was despised and rejected by mankind, a man of suffering, and familiar with pain. Like one from whom people hide their faces he was despised, and we held him in low esteem."
Compare this to Isaiah 49:7:
"This is what the Lord says—the Redeemer and Holy One of Israel—to him who was despised and abhorred by the nation, to the servant of rulers: “Kings will see you and stand up, princes will see and bow down, because of the Lord, who is faithful, the Holy One of Israel, who has chosen you.”
Also compare it to Psalm 22:6:
"But I am a worm and not a man, scorned by everyone, despised by the people."
Then, going on to Isaiah 53:4:
"Surely he took up our pain and bore our suffering, yet we considered him punished by God, stricken by him, and afflicted."
Compare that to Matthew 8:17:
"This was to fulfill what was spoken through the prophet Isaiah: “He took up our infirmities and bore our diseases.”
In relation to this, look at Isaiah 1:5-6:
"Why should you be beaten anymore? Why do you persist in rebellion? Your whole head is injured, your whole heart afflicted. From the sole of your foot to the top of your head there is no soundness—only wounds and welts and open sores, not cleansed or bandaged or soothed with olive oil."
I already mentioned Isaiah 53:5, so let's go on to 53:6, in order to look at the surrounding verses, instead of just the one verse.
"We all, like sheep, have gone astray, each of us has turned to our own way; and the Lord has laid on him the iniquity of us all." (Isaiah 53:6)
Compare this to Psalm 119:176:
"I have strayed like a lost sheep. Seek your servant, for I have not forgotten your commands."
Also compare Jeremiah 50:6:
“My people have been lost sheep; their shepherds have led them astray and caused them to roam on the mountains. They wandered over mountain and hill and forgot their own resting place."
And compare Jesus' parable in Luke 15:3-7:
"Then Jesus told them this parable: “Suppose one of you has a hundred sheep and loses one of them. Doesn’t he leave the ninety-nine in the open country and go after the lost sheep until he finds it? And when he finds it, he joyfully puts it on his shoulders and goes home. Then he calls his friends and neighbors together and says, ‘Rejoice with me; I have found my lost sheep.’ I tell you that in the same way there will be more rejoicing in heaven over one sinner who repents than over ninety-nine righteous persons who do not need to repent."
Also compare this to Ezekiel 34:1-6:
"The word of the Lord came to me: “Son of man, prophesy against the shepherds of Israel; prophesy and say to them: ‘This is what the Sovereign Lord says: Woe to you shepherds of Israel who only take care of yourselves! Should not shepherds take care of the flock? You eat the curds, clothe yourselves with the wool and slaughter the choice animals, but you do not take care of the flock. You have not strengthened the weak or healed the sick or bound up the injured. You have not brought back the strays or searched for the lost. You have ruled them harshly and brutally. So they were scattered because there was no shepherd, and when they were scattered they became food for all the wild animals. My sheep wandered over all the mountains and on every high hill. They were scattered over the whole earth, and no one searched or looked for them."
Isaiah 9:6-7 – “For a child is born to us, a son is given to us. And the government will rest on His shoulders. These will be His royal titles: Wonderful Counselor, Mighty God, Everlasting Father, Prince of Peace. His ever expanding, peaceful government will never end. He will rule forever with fairness and justice from the throne of His ancestor David. The passionate commitment of the Lord Almighty will guarantee this!”
And this is quoted in Matthew 12:18-21:
“Here is my servant whom I have chosen, the one I love, in whom I delight; I will put my Spirit on him, and he will proclaim justice to the nations. He will not quarrel or cry out; no one will hear his voice in the streets. A bruised reed he will not break, and a smoldering wick he will not snuff out, till he has brought justice through to victory. In his name the nations will put their hope.”
Isaiah 53, also known as the “Suffering Servant,” has been long understood by the historical Rabbis of Judaism to speak of the Redeemer who will one day come to Zion.
The Babylonian Talmud says: "The Messiah, what is his name? The Rabbis say, The Leper Scholar, as it is said, ‘surely he has borne our griefs and carried our sorrows: yet we did esteem him a leper, smitten of God and afflicted...'" (Sanhedrin 98b).
Midrash Ruth Rabbah says: "Another explanation (of Ruth 2:14): He is speaking of king Messiah; ‘Come hither,' draw near to the throne; ‘and eat of the bread,' that is, the bread of the kingdom; ‘and dip thy morsel in the vinegar,' this refers to his chastisements, as it is said, `But he was wounded for our transgressions, bruised for our iniquities.'"
The Targum Jonathan says: "Behold my servant Messiah shall prosper; he shall be high and increase and be exceedingly strong."
The Zohar says: "’He was wounded for our transgressions,' etc....There is in the Garden of Eden a palace called the Palace of the Sons of Sickness; this palace the Messiah then enters, and summons every sickness, every pain, and every chastisement of Israel; they all come and rest upon him. And were it not that he had thus lightened them off Israel and taken them upon himself, there had been no man able to bear Israel's chastisements for the transgression of the law: and this is that which is written, `Surely our sicknesses he hath carried.'"
The great (Rambam) Rabbi Moses Maimonides says: "What is the manner of Messiah's advent...there shall rise up one of whom none have known before, and signs and wonders which they shall see performed by him will be the proofs of his true origin; for the Almighty, where he declares to us his mind upon this matter, says, `Behold a man whose name is the Branch, and he shall branch forth out of his place' (Zechariah 6:12). And Isaiah speaks similarly of the time when he shall appear, without father or mother or family being known, He came up as a sucker before him, and as a root out of dry earth, etc....in the words of Isaiah, when describing the manner in which kings will harken to him, At him kings will shut their mouth; for that which had not been told them have they seen, and that which they had not heard they have perceived."
Unfortunately, modern Rabbis of Judaism believe that the “Suffering Servant” of Isaiah 53 refers perhaps to Israel, or to Isaiah himself, or even Moses or another of the Jewish prophets. But Isaiah is clear - he speaks of the Messiah, as many ancient rabbis concluded.
The second verse of Isaiah 53 confirms this clarity. The figure grows up as “a young plant, and like a root out of dry ground.” The shoot springing up is beyond reasonable doubt a reference to the Messiah, and, in fact, it is a common Messianic reference in Isaiah and elsewhere. The Davidic dynasty was to be cut down in judgment like a felled tree, but it was promised to Israel that a new sprout would shoot up from the stump. King Messiah was to be that sprout.
Beyond doubt, the “Suffering Servant” of Isaiah 53 refers to Messiah. He is the one highly exalted before whom kings shut their mouths. Messiah is the shoot who sprung up from the fallen Davidic dynasty. He became the King of Kings. He provided the ultimate atonement.
Isaiah 53 must be understood as referring to the coming Davidic King, the Messiah. King Messiah was prophesied to suffer and die to pay for our sins and then rise again. He would serve as a priest to the nations of the world and apply the blood of atonement to cleanse those who believe. There is One alone to whom this can refer, Jesus Christ!
Those who confess him are his children, his promised offspring, and the spoils of his victory. According to the testimony of the Jewish Apostles, Jesus died for our sins, rose again, ascended to the right hand of God, and he now serves as our great High Priest who cleanses us of sin (Hebrew 2:17; 8:1). Jesus, the Jewish Messiah, is the one Isaiah foresaw.
Rabbi Moshe Kohen Ibn Crispin said, “This rabbi described those who interpret Isaiah 53 as referring to Israel as those "having forsaken the knowledge of our Teachers, and inclined after the `stubbornness of their own hearts,' and of their own opinion, I am pleased to interpret it, in accordance with the teaching of our Rabbis, of the King Messiah. This prophecy was delivered by Isaiah at the divine command for the purpose of making known to us something about the nature of the future Messiah, who is to come and deliver Israel, and his life from the day when he arrives at discretion until his advent as a redeemer, in order that if anyone should arise claiming to be himself the Messiah, we may reflect, and look to see whether we can observe in him any resemblance to the traits described here; if there is any such resemblance, then we may believe that he is the Messiah our righteousness; but if not, we cannot do so.”
Here is another example that addresses your original question of verses in the Old Testament that talk about a Suffering Messiah:
“All who see Me ridicule Me. They shoot out the lip, they shake the head, saying, ‘He trusted in the Lord. Let Him rescue Him. Let Him deliver Him, since He delights in Him!’” (Psalm 22:7-8)
It was fulfilled here:
“When they had twisted a crown of thorns, they put it on His head, and a reed in His right hand. And they bowed the knee before Him and mocked Him saying, ‘Hail, King of the Jews!’” (Matthew 27:29)
“In the same way the chief priests, the teachers of the law and the elders mocked him. ‘He saved others,’ they said ‘but he can’t save Himself! He’s the King of Israel! Let him come down now from the cross, and we will believe in him. He trusts in God. Let God rescue Him now if He wants…’” (Matthew 27:41-43)
Not only did the New Testament authors realize that God is a Triune Being, but even Genesis 1:26 implies this:
“Then God said, “Let us make man in our image, after our likeness. And let them have dominion over the fish of the sea and over the birds of the heavens and over the livestock and over all the earth and over every creeping thing that creeps on the earth.”
"Us" cannot mean the angels, because God made man in His image, not in the image of angels. Not only that, but angels do not create humans.
In Genesis 1:1, the Hebrew plural noun "Elohim" is used. In Genesis 1:26, 3:22, 11:7 and Isaiah 6:8, the plural pronoun for “us” is used. The word "Elohim" and the pronoun “us” are plural forms, definitely referring in the Hebrew language to more than two. This denotes the aspect of plurality in God.
Christians believe in one God, Who is unique from any creature in that He is a Triune Being, consisting of three Persons. Not persons like human beings are persons, because with human beings, one person = one being. But not all beings are the same. Fish don't have feathers or fur, and birds do not have gills or scales. Man was made in God's image, but that doesn't mean man is exactly like God in every way. Man is not omniscient, omnipresent, or omnipotent. Man does not live outside of the confines of time and space. Man is flesh and blood, whereas God is not. Similarly, God is a Being consisting of three Persons. The only reason we call them "Persons" is because that is the closest term we can use to understand the concept. Just like we call Jesus the "Son" of God, even though Jesus is not God's biological son, contrary to what the Mormon cult believes, and contrary to what Muslims mistakenly think that Christians believe. "Son" is more of a spiritual son than a biological son, and is just the closest term we have to understand that concept. The same applies to calling God "Father." God does not have any biological children; neither does He have a wife.
Going on, Isaiah 48:16 mentions the Holy Spirit:
"Draw near to me, hear this: from the beginning I have not spoken in secret, from the time it came to be I have been there.” And now the Lord God has sent me, and his Spirit."
Isaiah 61:1 also mentions the Holy Spirit:
"The Spirit of the Lord God is upon me, because the Lord has anointed me to bring good news to the poor; he has sent me to bind up the brokenhearted, to proclaim liberty to the captives, and the opening of the prison to those who are bound."
In fact, in Isaiah 48:16 and 61:1, the Son is speaking while making reference to the Father and the Holy Spirit. 48:16 says, "from the beginning I have not spoken in secret," and "from the time it came to be [the beginning] I have been there." 61:1 talks about the Son/Messiah and says, "the Lord has anointed me to bring good news to the poor; he has sent me to bind up the brokenhearted, to proclaim liberty to the captives, and the opening of the prison to those who are bound."
Luke 4:14-19 makes reference to this:
"And Jesus returned in the power of the Spirit to Galilee, and a report about him went out through all the surrounding country. And he taught in their synagogues, being glorified by all. And he came to Nazareth, where he had been brought up. And as was his custom, he went to the synagogue on the Sabbath day, and he stood up to read. And the scroll of the prophet Isaiah was given to him. He unrolled the scroll and found the place where it was written, “The Spirit of the Lord is upon me, because he has anointed me to proclaim good news to the poor. He has sent me to proclaim liberty to the captives and recovering of sight to the blind, to set at liberty those who are oppressed, to proclaim the year of the Lord’s favor.”
And in verse 21, guess what Jesus says?
"He began by saying to them, “Today this scripture is fulfilled in your hearing.”
Jesus was claiming that Isaiah 61:1 was talking about Him!
And in verses 23-29, it says:
"Jesus said to them, “Surely you will quote this proverb to me: ‘Physician, heal yourself!’ And you will tell me, ‘Do here in your hometown what we have heard that you did in Capernaum.’” “Truly I tell you,” he continued, “no prophet is accepted in his hometown. I assure you that there were many widows in Israel in Elijah’s time, when the sky was shut for three and a half years and there was a severe famine throughout the land. Yet Elijah was not sent to any of them, but to a widow in Zarephath in the region of Sidon. And there were many in Israel with leprosy in the time of Elisha the prophet, yet not one of them was cleansed—only Naaman the Syrian.” All the people in the synagogue were furious when they heard this. They got up, drove him out of the town, and took him to the brow of the hill on which the town was built, in order to throw him off the cliff. But he walked right through the crowd and went on his way."
Did you get that? Jesus' point was that when Israel rejected God's messenger of redemption, God sent Him to the Gentiles---and so it will be again if they refuse to accept Jesus. For example, in Luke 10:13-15, Jesus says:
“Woe to you, Chorazin! Woe to you, Bethsaida! For if the miracles that were performed in you had been performed in Tyre and Sidon, they would have repented long ago, sitting in sackcloth and ashes. But it will be more bearable for Tyre and Sidon at the judgment than for you. And you, Capernaum, will you be lifted to the heavens? No, you will go down to Hades."
Back to Luke 4, because of Jesus' condemnation of Israel and favorable attitude toward Gentiles, the Jews tried to throw Jesus off a cliff! But because Jesus' time had not yet come (i.e., to die on the cross for men's sins), Jesus was able to merely walk right through the murderous crowd!
Going on, Matthew 28:19 lists the Persons of the Trinity:
"Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit."
2 Corinthians 13:14 also mentions the Persons of the Trinity:
"The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with you all."
Jesus said there is only one God:
"How can you believe if you accept praise from one another, yet make no effort to obtain the praise that comes from the only [monos] God?" (John 5:44)
"After Jesus said this, he looked toward heaven and prayed: "Father, the time has come. Glorify your Son, that your Son may glorify you. For you granted him authority over all people that he might give eternal life to all those you have given him. Now this is eternal life: that they may know you, the only [monos] true God, and Jesus Christ, whom you have sent. I have brought you glory on earth by completing the work you gave me to do. And now, Father, glorify me in your presence with the glory I had with you before the world began." (John 17:1-5)
Notice that in the above verses, Jesus refers to God as "Father" and calls Him "the only true God," yet He also refers to Himself as the Son, and says that the Father has given Him authority over all people to grant eternal life!
In both John 5:44 and John 17 (above), the word "monos" is used to describe God, which means "alone."
However, in the following verses, the word "hen" is used instead:
"The foremost is, 'Hear, O Israel! The Lord our God is one [hen] Lord." (Mark 12:29)
"I and the Father are one [hen]." (John 10:30)
In the New Testament, this is the Greek equivalent to the Hebrew word for 'one.' In Matthew 19:5, Jesus quotes Genesis 2:24 about a husband and wife becoming one flesh; the word used is 'hen.' Jesus prays that believers will be one, even as He and the Father are one. He did not mean their persons would be fused together; it means spiritually united. They are not one Person, but in nature they are unified. The God of the Old Testament is a united one. The God of the New Testament is a united one. This is what is meant by God being one.
In the Old Testament, teachings were focused on God being one in contrast to the polytheism of the nations that surrounded Israel. There are statements that speak of the plurality of this *one* God in the Old Testament record.
However, it is only when we come to the New Testament that this one in unity is explained.
Where John 10:30 says, "I and my Father are one," this is not a numerical one. Jesus is not saying He is the Father. They are not one person, but in nature they are unified. It actually reads "we are one" in Greek. The first-person plural 'esmen' means ‘we are.’ Again, this is a unity in nature, not a numerical statement.
The word 'one' in Greek is 'Hen,' and it is a neuter nominative, so it refers to one in essence and nature and kind. In John 10:30, it is saying that Jesus is deity just as the Father is. He went on to explain that he is the Son of God, and the Pharisees understood his claim of making himself out to be equal with the Father. That's why, in John 10:31, it says that the Jews took up stones to stone Jesus.
In the Old Testament, God is described as one. Deuteronomy 6:4 says, "Hear, O Israel: The Lord our God, the Lord is one." (Or, "The Lord our God is one Lord.") The phrase "one Lord" is preceded in the Hebrew by 'elohenu;' it is "our God is one." The word for 'one' is not a numerical one, but is actually a united one. The Hebrew word for 'one' is 'echad,' which comes from the root word 'achad,' which means 'to unify or collect together' (the intensive reflexive form signifying 'to unite'). If this was meant to be a strict numerical statement, the Holy Spirit would have had Moses use the word 'yachid,' which means an absolute one; single; only one. 'Yachid' is used twelve times in the Scriptures; but not once is it used for YHWH God!
An example of this 'united one' is Genesis 1:5, where evening and morning are called one day (a combination of two parts to make one). They are both considered a day, yet we can distinguish them as different phases.
Another example is Genesis 2:24, where Adam and Eve become one flesh. Here, two personalities come together in marriage and become one---not one person, but one in unity. God sees them as one, even though they are not physically fused together like Siamese twins. So, if we say 'echad' in Deuteronomy 6:4 ("one") means a numerical one, then Siamese twins would be the only consideration for our understanding of Genesis 2:24 for man and wife becoming one flesh.
Other instances of 'echad,' which is also used for "one" in Deuteronomy 6:4 to describe God, is Genesis 11:6, where the people are one; or Ezra 2:64, where the whole assembly of Israel is like one.
Yet another example is Numbers 13:23, where, according to their view, when the spies went over into the land of Canaan, they brought back "one" grape (Hebrew: 'eschal echad.') It says that two of them carried it on a pole between them, along with pomegranates and figs. Why would they bring just one grape? Was one grape really that huge? Can anyone actually think it was a numerical statement? But in fact, it means a 'cluster' of grapes.
Other examples are Psalm 133:1, where the brethren is to dwell as one (in unity); 1 Samuel 3:17, where they are called one company; 2 Samuel 2:25, one troop; 1 Kings 7:42, one tribe; and in 1 Kings 11:13, Israel is called one nation.
Yet another example of 'echad' for "one" is Ezekiel 37:17, where Ezekial is told to put two sticks together, so that combined, they become 'one' stick, showing that the nation would be unified. In all these examples, it is not a strict singular meaning. This same word is applied to the 'one' God, and is clearly used as a compound unity.
The word for a strict single is 'yachid.' It's used in Genesis 22:2: "Take thy one and only son." This can also be used for God's only Son being unique and one-of-a-kind.
God is above and beyond all of us. None of us can fully and completely comprehend God. If we could, then He wouldn't be God. There is one and only one God. God eternally exists in three distinct Persons. In other words, God is said to be three Persons in one essence, nature, or being. The Father is God, the Son is God, and the Holy Spirit is God. The Father is not the Son, the Son is not the Father, the Father is not the Spirit. Jesus is not a lesser deity than the Father. The Father, Son and Holy Spirit are co-equal in nature. However, the Holy Spirit glorifies the Son and the Son glorifies the Father. The Trinity is not 1 + 1 + 1 (= 3) , but rather 1 x 1 x 1 (= 1).