ישעיהו מא:ח פירוש: רש״י ואבן עזרא

But you, Israel My servant and I am obliged to help you. The end of this sentence is (infra 10): “Do not fear.” This appears to me to be the sequence of the section according to its simple meaning. But the Midrash Aggadah in Gen. Rabbah 44:7 expounds the entire section as alluding to Malchizedek and Abraham.

But thou, Israel, etc. Those are worshippers of idols, says the prophet, but thou, Israel, art my servant; the name of Abraham is mentioned here, because he also was taken out from the midst of idolaters.

[5] Islands saw the war and feared. Shem [Malchizedek] feared Abraham, lest he say to him, You begot these wicked men in the world. And Abraham feared Shem, since he slew his sons, the people of Elam, who was descended from Shem.