But if anyone has doubts about eating and then eats, that condemns him at once; it was not faith that induced him to eat, and any action that is not based on faith is a sin.
and apart from faith it is impossible to satisfy him, for the man who draws near to God must believe that he exists and that he does reward those who seek him.
But remember, it is not everyone who has this 'knowledge.' Some who have hitherto been accustomed to idols eat the food as food which has been really offered to an idol, and so their weaker conscience is contaminated.