Now about food sacrificed to idols: We know that "We all possess knowledge." But knowledge puffs up while love builds up. (NIV)
NOW ABOUT food offered to idols: of course we know that all of us possess knowledge [concerning these matters. Yet mere] knowledge causes people to be puffed up (to bear themselves loftily and be proud), but love (affection and goodwill and benevolence) edifies and builds up and encourages one to grow [to his full stature]. (AMP)
Now as touching things offered unto idols, we know that we all have knowledge. Knowledge puffeth up, but charity edifieth. (KJV)