The NASB translates Isaiah 53:11, in part, as “by His knowledge the Righteous One, My Servant, will justify the many.” Based on the discussion in Hagglund’s Isaiah 53 in the Light of Homecoming After Exile (Forschungen Zum Alten Testament) (73-77), I find this questionable on two grounds.
First, there is the oddity that the knowledge of the Servant seems to be the instrument for the justification of the many. But the rest of the passage talks about the Servant’s “bearing” of sin and infirmity, and besides how can the Servant’s knowledge of something produce the justification of others? The best solution here is the simple one of taking “by His knowledge” with the preceding clause: “He will see and be satisfied.” There are still some complications, but the notion that the Servant observes, knows, and is satisfied by what He knows is far clearer than the notion that knowledge is somehow an instrument of atonement or justification.
Second, the Hebrew of clause has “to” (a lamed, le ) before many, and might be rendered “the Righteous One, My Servant, will justify to the many.” The NASB leaves the preposition untranslated, leaving the impression that “many” is simply the object of “justify.” But the clause is unusually constructed.
1 Kings 8:32 is a prayer that the righteous (innocent) should be justified by being rewarded according to their righteousness. The object of “justify” is “the righteous,” and there is no lamed. Nor is there a lamed in Yahweh’s declaration “I will not justify the guilty” (Proverbs 17:15). “Many” is likely not the direct, but an indirect object of “justify.”
But then who or what is being justified, if not the many? Hagglund’s answer is convincing. In a survey of other texts using zadaq in the hiphil (the verb construction in Isaiah 53:11), he shows that this verb form refers to innocents who are shown, proven, or declared to be innocent. “Vindicate” is usually a good translation. Hence in Isaiah 53:11: “the Righteous One, My Servant, will be vindicated to the many.”
This fits the overall story-line of the passage, which is all about the people’s recognition that the Servant is innocent and they are guilty. This is the exaltation of the Servant with which the passage begins: Despised, rejected, treated as an outcast to God and man, the Servant is proven innocent and many of the people penitently acknowledge His innocent.