1 Peter 2:19

19For this is thankworthy The word grace or favor, has the meaning of praise; for he means that no grace or praise shall be found before God, if we bear the punishment which we have by our faults deserved; but that they who patiently bear injuries and wrongs are worthy of praise and accepted by God. (32) To testify that it was acceptable to God, when any one from conscience towards God persevered in doing his duty, though unjustly and unworthily treated, was at that time very necessary; for the condition of servants was very hard: they were counted no better than cattle. Such indignity might have driven them to despair; the only thing left for them was to look to God.

For conscience towards God means this, that one performs his duty, not from a regard to men, but to God. For, when a wife is submissive and obedient to her husband, in order to please him, she has her reward in this world, as Christ says of the ambitious, who looked to the praise of men, (Matthew 6:16.) The same view is to be taken of other cases: When a son obeys his father in order to secure his favor and bounty, he will have his reward from his father, not from God. It is, in short, a general truth, that what we do is approved by God, if our object be to serve him, and if we are not influenced by a regard to man alone. Moreover, he who considers that he has to do with God, must necessarily endeavor to overcome evil with good. For, God not only requires that we should be such to every one as he is to us, but also that we should be good to the unworthy and to such as persecute us.