Albert Barnes Commentary 1 Corinthians 3:17

"If any man destroyeth the temple of God, him shall God destroy; for the temple of God is holy, and such are ye." — 1 Corinthians 3:17 (ASV)

If any man defile, etc. Or, destroy, corrupt, fyeirei. The Greek word is the same in both parts of the sentence. If any man destroy the temple of God, God shall destroy him. This is presented in the form of an adage or proverb. And the truth stated here is based on the fact that the temple of God was inviolable; that temple was holy; and if any man subsequently destroyed it, it might be presumed that God would destroy him. The figurative sense is, "If any man by his doctrines or precepts shall pursue such a course as tends to destroy the church, God shall severely punish him."

For the temple of God is holy. The temple of God is to be regarded as sacred and inviolable. This was unquestionably the common opinion among the Jews respecting the temple at Jerusalem; and it was the common doctrine of the Gentiles respecting their temples. Sacred places were regarded as inviolable; and this general truth Paul applies to the Christian church in general. Locke supposes that Paul had particular reference here to the false teachers in Corinth. But the expression, "If any man," is equally applicable to all other false teachers as to him.

Which temple you are. This proves that though Paul regarded them as lamentably corrupt in some respects, he still regarded them as a true church—as a part of the holy temple of God.