The suffering servant
One of the most impressive themes developed by Second Isaiah is that of the suffering servant. There are three poems (Isaiah 42.1-4, 49.1-6, 50.4-11) in which the prophet, who lived in the age of the Babylonian Captivity, describes this pious man, God's "chosen one" who will bring justice to all nations, who has an "instructed tongue" and a "mouth like a sharpened sword", and who has been able to suffer humiliation because he relied on God. So far, there is nothing unusual; the problem is the shocking fourth poem which, in the first and the third part, praises the servant, and in the second part describes his suffering.
It is impossible to identify the servant with a known historical person. However, it is certain that the servant's fate deeply shocked the second Isaiah, who came to the conclusion that a just man had been punished by God for the wickedness of others. This was a completely new idea, which was to become very influential.
The exact identification is irrelevant for our purposes; what matters is that the poems about the suffering servant contained material that could be used in messianic speculations, words like "chosen one", "servant", "branch", "root" and "shoot" (cf. the words of first Isaiah about the shoot of Jesse).
The suffering servant
[52.13] See, my servant will act wisely; he will be raised and lifted up and highly exalted.
[52.14] Just as there were many who were appalled at him - his appearance was so disfigured beyond that of any man and his form marred beyond human likeness -
[52.15] so will he sprinkle many nations, and kings will shut their mouths because him. For what they were not told, they will see, and what they have not heard, they will understand.
[53.1] Who has believed our message and to whom has the arm of the Lord been revealed?
[53.2] He grew up 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.
[53.3] He was despised and rejected by men, a man of sorrows, and familiar with suffering. Like one from whom men hide their faces he was despised, and we esteemed him not.
[53.4] Surely he took up our infirmities and carried our sorrows, yet we considered him stricken by God, smitten by Him, and afflicted. But he was pierced for our transgressions, he was crushed for our iniquities;
[53.5] the punishment that brought us peace was upon him, and by his wounds we are healed.
[53.6] We all, like sheep, have gone astray, each of us has turned to his own way, and the Lord has laid on him the iniquity of us all.
[53.7] He was oppressed and afflicted, yet he did not open his mouth; he was led like a lamb to the slaughter, and as a sheep before his shearers is silent, so he did not open his mouth.
[53.8] By oppression and judgment he was taken away.
And who can speak of his descendants? For he was cut off from the land of the living; for the transgression of my people he was stricken.
[53.9] He was assigned a grave with the wicked, and with the rich in his death, though he had done no violence, nor was any deceit in his mouth.
[53.10] Yet it was the Lord's will to crush him and cause him suffer, and though the Lord makes his life a guilt offering, he will see his offspring and prolong his days, and the will of the Lord will prosper in his hand.
[53.11] After the suffering of his soul, he will see the light of life and be satisfied; by his knowledge My righteous servant will justify many, and he will bear their iniquities.
[53.12] Therefore I will give him a portion among the great, and he will divide the spoils with the strong, because he poured out his life unto death, and was numbered with the transgressors. For he bore the sin of many, and made intercession for the transgressors.