Moses
Exodus 32:26ESV·traditional attribution

then Moses stood in the gate of the camp and said, “Who is on the LORD’s side? Come to me.” And all the sons of Levi gathered around him.

Matthew Henry Presbyterian @wholebiblehenry

Moses, having shown his just indignation against the sin of Israel by breaking the tables and burning the calf, now proceeds to reckon with the sinners and to call them to an account, herein acting as the representative of God, who is not only a holy God, and hates sin, but a just God, and is engaged in honour to punish it, Isa 59:18. Now, I.

Commenting on Exodus 32:21-29

John Gill Reformed Baptist @doctorgill

And he said unto them, thus saith the Lord God of Israel,.... The following orders are given by Moses, not of himself the chief magistrate, and as the effect of heat and passion, but there were from the Lord, who was Israel's God and King; he had them expressly from him, or by an impulse on his spirit, or in such a way and manner...

Jamieson-Fausset-Brown Reformed @jfbcommentary

Moses stood in the gate of the camp, and said--The camp is supposed to have been protected by a rampart after the attack of the Amalekites. Who is on the Lord's side? let him come unto me--The zeal and courage of Moses was astonishing, considering he opposed an intoxicated mob.