Patristic

Didache 1:1-6

1. There are two Ways, one of Life and one of Death, and there is a great difference between the two Ways.
2. The way of life is this:" First, you shalt love the God who made thee, secondly, thy neighbor as thyself; and whatsoever thou wouldst not have done to thyself, do not thou to another."
3. Now, the teaching of these words is this: "Bless those that curse you, and pray for your enemies, and fast for those that persecute you. For what credit is it to you if you love those that love you? Do not even the heathen do the same?" But, for your part, "love those that hate you," and you will have no enemy.
4. "Abstain from carnal" and bodily "lusts." "If any man smite thee on the right cheek, turn to him the other cheek also," and thou wilt be perfect. "If any man impress thee to go with him one mile, go with him two. If any man take thy coat, give him thy shirt also. If any man will take from thee what is thine, refuse it not," not even if thou canst.
5. Give to everyone that asks thee, and do not refuse, for the Father's will is that we give to all from the gifts we have received. Blessed is he that gives according to the mandate; for he is innocent; but he who receives it without need shall be tried as to why he took and for what, and being in prison he shall be examined as to his deeds, and "he shall not come out thence until he pay the last farthing."
6. But concerning this it was also said, "Let thine alms sweat into thine hands until thou knowest to whom thou art giving."

Rabbinic

Shabbat 31a

There was another incident involving one gentile who came before Shammai and said to Shammai: Convert me on condition that you teach me the entire Torah while I am standing on one foot. Shammai pushed him away with the builder’s cubit in his hand. This was a common measuring stick and Shammai was a builder by trade. The same gentile came before Hillel. He converted him and said to him: That which is hateful to you do not do to another; that is the entire Torah, and the rest is its interpretation. Go study.