Returning Ribbit

The Ramban in mitzvot asseh that the Rambam forgot to count #12 lists the commandment to return ribbit which is derived from the words וְחֵ֥י אָחִ֖יךָ עִמָּֽךְ (25:36.)  The Megillas Esther defends the opinion of the Rambam that its not counted as a mitzvah because its included in the commandment to return stolen goods.  What is this debate about? 

The Ritvah Babba Metziah 61a brings the opinion of the Geonim that the borrower can’t be מוחל the money that the lender owes him for taking ribbit.  He explains their reason is that its not a monetary obligation to return the ribbit, it’s an obligation like any other בין אדם למקום obligation.  This would fit with the Ramban that this is a separate mitzvah to return ribbit, it’s not a monetary obligation.  The Rambam goes לשיטתו according to the Megillas Esther that is a monetary obligation and holds מחילה works (Malveh 4:13.)

The Shulchan Aruch (based upon Rashba, 161:5) rules that we don’t collect money from the lender; we will force him to pay.  If it was a pure monetary obligation, we should collect from the lender like any money owned for a dept.  It would seem that the Shulchan Aruch holds it’s a mere mitzvah obligation to return the ribbit.  However, he rules (160:5) like the Rosh that the borrower can forgive the ribbit that the lender should pay him back.  From there it seems that it’s a monetary obligation, so what is it?

We see that the Shulchan Aruch holds that it is a mitzvah to return the ribbit.  However, we define the money as ribbit based upon the rules of choshen mishpat.  If the borrower forgives the money, then it is not considered as if there is any money of ribbit in the hands of the lender (see Likutay Sichos volume 12.)

There is of course more to say on this topic, תן לחכם וכו'.   

For those interested  see this link.