Translation:Shulchan Aruch/Yoreh Deah/160
The great prohibition involved in interest-lending and the extant to which one must be careful to avoid it: 23 Sub-Sections
edit160:1 One must take great care not to transgress the prohibition of interest. There are several individual Biblical prohibitions at play, which may cause either the borrower, the deliverer, the guarantor or the witness to be liable. NOTE:: There is no difference whether the lender is wealthy or poor (HAGHOT MAYMANEE, CH. 4 OF MALVE LOVEH).
והא דלוה עובר דוקא ברבית דאורייתא אבל ברבית דרבנן אינו עובר אלא משום לפני עור וגו' (ר"ן פ' זה בורר ובנ"י פא"נ וכ"כ ר' ירוחם ני"ח):