Moses
Exodus 4:8ESV·traditional attribution

“If they will not believe you,” God said, “or listen to the first sign, they may believe the latter sign.

John Calvin Reformed @genevareformer

8. And it shall come to pass, if they will not believe thee. In these words God took away from Moses every handle for doubt; as much as to say, that he was sufficiently provided and strengthened to overcome the stubbornness of the people; and yet, heaping up the measure to overflowing, he afterwards added a third sign, from whence Moses might attain full confidence...

Matthew Henry Presbyterian @wholebiblehenry

It was a very great honour that Moses was called to when God commissioned him to bring Israel out of Egypt; yet he is with difficulty persuaded to accept the commission, and does it at last with great reluctance, which we should rather impute to a humble diffidence of himself and his own sufficiency than to any unbelieving distrust of God and his word and power.

Commenting on Exodus 4:1-9

John Gill Reformed Baptist @doctorgill

And it shall come to pass, if they will not believe thee,.... Will not give credit to the commission he had from God, but question the truth of it: neither hearken to the voice of the first sign; which miracle wrought, spoke plain enough that he that wrought it, or for whose sake it was wrought, must be one come from God, or such a...