Midrash su Levitico 25:37

3) "and your brother shall live with you": This was expounded by Ben Patori: If two men were walking along the road and one of them had only a kiton of water — If one of them drinks it, he will reach the settlement; if both of them drink it, they will both die — Ben Patori expounded: Let them both drink it and die, it being written "and your brother shall live with you" (i.e., "as you do"). R. Akiva said to him "and your brother shall live with you" — your life comes before that of your neighbor. (Vayikra 25:37) ("Your money you shall not give him on interest, and on increase you shall not give your food.") "your money": and not the money of others (i.e., gentiles); "and your food": and not that of others. — But perhaps (the meaning is) "your money," but not the money of ma'aser; "your food," but not animal food! (This cannot be maintained, for it is written [Devarim 23:20]) "interest of money" — to include the money of ma'aser; "interest of food" — to include animal food. "and on increase you shall not give your food. (Devarim 23:38) I am the L–rd" — whence they stated: One who takes upon himself the yoke of (shunning) interest takes upon himself the yoke of Heaven, and one who divests himself of the yoke of (shunning) interest divests himself of the yoke of Heaven. (Vayikra 25:38) ("I am the L–rd your G d, who took you out of the land of Egypt to give to you the land of Canaan, to be a G d to you.") "I am the L–rd your G d, who took you out": It is on this condition that I took you out of the land of Egypt — that you take upon yourselves the mitzvah of (shunning) interest. For all who acknowledge the mitzvah of (shunning) interest acknowledge the exodus from Egypt, and all who deny the mitzvah of (shunning) interest, it is as if they would deny the exodus from Egypt.

There were men in Jerusalem, also, who loaned money on interest, as it is said: Thy silver is become dross (Isa. 1:22). What was their fate? Refuse silver shall men call them, because the Lord hath rejected them (Jer. 6:30). Therefore Scripture states: Thy silver is become dross, It is also written: They shall cast their silver and their gold into the streets (Ezek. 7:19). Why? Because they had transgressed the law, as it is said: Thou shalt not give him thy money upon interest (Lev. 25:37).

"Do not impose interest upon him": What is the intent of this? (Leviticus 25:37) "Your money you shall not give him on interest" is an exhortation to the lender. Whence do we derive (the same for) the borrower? From (Ibid. 36) "You shall not take from him interest." This tells me only of an exhortation to the borrower and to the lender. Whence do we derive (the same for) the witnesses, the guarantors, and the scribe? From "Do not impose" — in any manner. From here they adduced: One who lends on interest is guilty of five transgressions: "You shall not give," "You shall not take," "You shall not impose interest upon him," "You shall not be as a creditor to him," (Leviticus 19:14) "You shall not place a stumbling block before the blind man." Just as the lender and the borrower transgress, so, the guarantor, the witnesses, and the scribe. R. Meir excludes the scribe. R. Yossi says: One who lends on interest and says to the scribe "Come and write," and to the witnesses "Sign" has no portion with Him who commanded against interest.