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 Abdullahibn Umar say, "If someone lends something, let the only condition bethat it is repaid." Translation Not Available

Book Ref: Muwatta Imam Malik Book 31 Hadith 1380
Web Ref:  Muwatta Imam Malik Book 31 Hadith 94