Isaiah 59:1
1Behold, the LORD’s hand is not shortened, that it can’t save; nor his ear dull, that it can’t hear.
The first word is Behold: look here, not at a weak God. Hand and ear are whole. Salvation is not stalled by divine inability.
The same Lord who answered “Here I am” to a true fast (58:9) has not gone deaf. If he does not save, the cause is not a shortened arm. The verse still invites a people to come; the next verse will name what blocks the coming.
Calvin: hypocrites accuse God of weakness or excessive severity. He shows he does not want power or will to save, but is prevented by their wickedness. Behold is emphatic, as if pointing with the finger. Supply the contrasts: his hand was never broken, his ear never grown dull.
God is always like himself, not wearied in doing good, power not diminished. We hinder the entrance of his grace. The slander belongs on our side of the line.