3:16,17 From other parts of the epistle, it appears that the false teachers among the Corinthians taught unholy doctrines. Such teaching tended to corrupt, to pollute, and destroy the building, which should be kept pure and holy for God. Those who spread loose principles, which render the church of God unholy, bring destruction upon themselves. Christ by his Spirit dwells in all true believers. Christians are holy by profession, and should be pure and clean, both in heart and conversation. He is deceived who deems himself the temple of the Holy Ghost, yet is unconcerned about personal holiness, or the peace and purity of the church.
17. If any … defile … destroy—rather as the Greek verb is the same in both cases, "destroy … destroy." God repays in kind by a righteous retaliation. The destroyer shall himself be destroyed. As temporal death was the penalty of marring the material temple (Le 16:2; Da 5:2, 3, 30), so eternal death is the penalty of marring the spiritual temple—the Church. The destroyers here (1Co 3:16, 17), are distinct from the unwise or unskilful builders (1Co 3:12, 15); the latter held fast the "foundation" (1Co 3:11), and, therefore, though they lose their work of superstructure and the special reward, yet they are themselves saved; the destroyers, on the contrary, assailed with false teaching the foundation, and so subvert the temple itself, and shall therefore be destroyed. (See on 1Co 3:10), [Estius and Neander]. I think Paul passes here from the teachers to all the members of the Church, who, by profession, are "priests unto God" (Ex 19:6; 1Pe 2:9; Re 1:6). As the Aaronic priests were doomed to die if they violated the old temple (Ex 28:43), so any Christian who violates the sanctity of the spiritual temple, shall perish eternally (Heb 12:14; 10:26, 31).
holy—inviolable (Hab 2:20).
which temple ye are—rather, "the which (that is, holy) are ye" [Alford], and, therefore, want of holiness on the part of any of you (or, as Estius, "to tamper with the foundation in teaching you") is a violation of the temple, which cannot be let to pass with impunity. Grotius supports English Version.