37 Let what you say be simply 'Yes' or 'No'; anything more than this comes from evil.

Love for Enemies

38 "You have heard that it was said, 'An eye for an eye and a tooth for a tooth.' 39 But I say to you, Do not resist one who is evil. But if any one strikes you on the right cheek, turn to him the other also; 40 and if any one would sue you and take your coat, let him have your cloak as well;

Matthew Henry's Commentary on Matthew 5:37-40

Commentary on Matthew 5:33-37

(Read Matthew 5:33-37)

There is no reason to consider that solemn oaths in a court of justice, or on other proper occasions, are wrong, provided they are taken with due reverence. But all oaths taken without necessity, or in common conversation, must be sinful, as well as all those expressions which are appeals to God, though persons think thereby to evade the guilt of swearing. The worse men are, the less they are bound by oaths; the better they are, the less there is need for them. Our Lord does not enjoin the precise terms wherein we are to affirm or deny, but such a constant regard to truth as would render oaths unnecessary.

Commentary on Matthew 5:38-42

(Read Matthew 5:38-42)

The plain instruction is, Suffer any injury that can be borne, for the sake of peace, committing your concerns to the Lord's keeping. And the sum of all is, that Christians must avoid disputing and striving. If any say, Flesh and blood cannot pass by such an affront, let them remember, that flesh and blood shall not inherit the kingdom of God; and those who act upon right principles will have most peace and comfort.