Charles Ellicott Commentary Isaiah 29:21

"that make a man an offender in [his] cause, and lay a snare for him that reproveth in the gate, and turn aside the just with a thing of nought." — Isaiah 29:21 (ASV)

That make a man an offender for a word ... —The words indicate that Isaiah had been accused, as Jeremiah was afterwards (Jeremiah 37:13), of being unpatriotic, because he had rebuked the sins of Israel and its rulers. Another interpretation suggests, “that make men sinners in word,” i.e., suborn false witnesses against him. The former seems preferable, but the general meaning of the passage is the same. The “snare” was laid for the “righteous man,” precisely because he “reproved in the gate:” i.e., preached in the open air in the places of public concourse, even in the presence of the rulers and judges as they sat there.

Turn aside the just. —The phrase is used in Exodus 23:6; Amos 5:12; Malachi 3:5, for the deliberate perversion of justice.

A thing of nought. —The Hebrew word is once more the tohu (“without form”) of Genesis 1:1. The accusations brought against the prophet were, as we say, incoherent, absolutely chaotic in their falsehood.