There are two ways, one of life and one of death, but a great difference between the two ways. The way of life, then, is this: First, you shall love God who made you; second, love your neighbor as yourself, and do not do to another what you would not want done to you. And of these sayings the teaching is this: Bless those who curse you, and pray for your enemies, and fast for those who persecute you. For what reward is there for loving those who love you? Do not the Gentiles do the same? But love those who hate you, and you shall not have an enemy. Abstain from fleshly and worldly lusts. If someone strikes your right cheek, turn to him the other also, and you shall be perfect. If someone impresses you for one mile, go with him two. If someone takes your cloak, give him also your coat. If someone takes from you what is yours, ask it not back, for indeed you are not able. Give to every one who asks you, and ask it not back; for the Father wills that to all should be given of our own blessings. Happy is he who gives according to the commandment, for he is guiltless. Woe to him who receives; for if one receives who has need, he is guiltless; but he who receives not having need shall pay the penalty, why he received and for what. And coming into confinement, he shall be examined concerning the things which he has done, and he shall not escape from there until he pays back the last penny. And also concerning this, it has been said, Let your alms sweat in your hands, until you know to whom you should give.
Didache (or The Lord’s Teaching Through the Twelve Apostles to the Nations)