It is narrated from Sayyiduna Ka'b (may Allah be pleased with him) that Abdullah bin Abi Hadrad owed him some money, and he demanded it from him until their voices rose. The Messenger of Allah (peace and blessings be upon him) passed by them and said: "O Ka'b!" and gestured with his hand as though indicating that he should let go of half. So he took half of his debt and left half.
Hadith Referenceالمعجم الكبير للطبراني / باب الكاف / 16228