Jews argue that the suffering servant in the book of Isaiah refers to the nation Israel because there are many preceding passages in Isaiah that refer to the servant as Israel, that is, the “tribes of Jacob” mentioned in Chapter 49:6 below:
“3 And he said unto me, Thou art my servant, O Israel, in whom I will be glorified. 4 Then I said, I have laboured in vain, I have spent my strength for nought, and in vain: yet surely my judgment is with the Lord, and my work with my God.
5 And now, saith the Lord that formed me from the womb to be his servant, to bring Jacob again to him, Though Israel be not gathered, yet shall I be glorious in the eyes of the LORD, and my God shall be my strength. 6 And he said, It is a light thing that thou shouldest be my servant to raise up the tribes of Jacob, and to restore the preserved of Israel: I will also give thee for a light to the Gentiles, that thou mayest be my salvation unto the end of the earth.”
Consider verse 6. It says that “It is a light thing that thou should be my servant to raise up the tribes of Jacob, and to restore the preserved of Israel.” If the servant in this passage (whom God formed from the womb, verse 5) is Israel, then Israel (tribes of Jacob) will raise itself up by it’s own bootstraps. And that is exactly what Israel and Jewish commentators on Isaiah 53 are attempting to do.