وَحَدَّثَنِي مَالِكٌ، عَنْ نَافِعٍ، أَنَّهُ سَمِعَ عَبْدَ اللَّهِ بْنَ عُمَرَ، يَقُولُ مَنْ أَسْلَفَ سَلَفًا فَلاَ يَشْتَرِطْ إِلاَّ قَضَاءَهُ ‏.‏

Yahya related to me from Malik from Nafi that he heard Abdullah ibn Umar say, "If someone lends something, let the only condition be that it is repaid