1 Corinthians 10:29

conscience, I say, not thine own, but the other's; for why is my liberty judged by another conscience? [Christianity did not forbid a man to retain his friendships among pagans, nor did it prohibit fellowship with them. If such a friend should ask a Christian to a meal in a private house and not to a sacrificial feast in an idol temple, the Christian need not trouble himself to ask whether the meat that was served was part of all idol sacrifice, for such a dining was in no sense an act of worship. If, however, some scrupulous Christian or half-converted person should point out that the meat was idolatrous, then it was not to be eaten, for the sake of the man who regarded it as idolatrous. But so far as the real question of liberty was concerned, each man's liberty is finally judged by his own conscience and not by that of another. Liberty may be waived for the sake of another's conscience, but it is never thus surrendered. Paul's teaching, therefore, is that food is not tainted, and so it is always right to eat it as food, but all the rites of idolatry are tainted, and the Christian must do nothing which gives countenance to those rites, and for the sake of others he must abstain from seeming to countenance them even when his own conscience acquits him of so doing.]