1 Corinthians 8:7

Howbeit there is not in every man that knowledge See note on 1 Corinthians 8:1.

for some with conscience of the idol Some editors read by familiarity withinstead of with conscience of. If so, we must understand the passage of Gentile converts, who by long habit had become so accustomed to the idea of the personality of the idol that they could not shake it off. The words unto this hourconfirm this reading. It was very difficult for Gentile converts to shake off their heathen notions. Many of the heresies of early times were due to these invincible prepossessions, as is also the belief in magic and witchcraft, which in all nations has long survived their conversion to Christianity. If, on the other hand, we read conscience, it means either (1) conscientious dread of becoming in any way connected with the idol, or (2) conscientious apprehension of his personality, as though the meat were in some sense his property, and the eating of it an act of worship.

and their conscience being weak is defiled He is mistaken in his idea that the idol has a real existence, but as long as he entertains that idea, he is bound to act up to it. Cf. Romans 15:14, -To him that esteemeth anything to be unclean, to him it is unclean. See also Romans 15:20; Romans 15:23 of the same chapter.