John Calvin Commentary Joshua 24:16

"And the people answered and said, Far be it from us that we should forsake Jehovah, to serve other gods;" — Joshua 24:16 (ASV)

And the people answered and said, etc. Here we see he had no reason to regret the option given, when the people, not swearing in the words of another, nor obsequiously submitting to extraneous dictation, declare that it would be an impious thing to revolt from God.

And thus it tends, significantly, to confirm the covenant when the people voluntarily lay the law upon themselves.

The substance of the answer is that since the Lord has, by a wonderful redemption, purchased them for himself as a peculiar people, has constantly lent them his aid, and shown that he is among them as their God, it would be detestable ingratitude to reject him and revolt to other gods.