It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) that a man seized his debtor over ten dinars and said: By Allah, I will not let you go until you pay me my due or bring a guarantor. The narrator said: So the Prophet (peace and blessings be upon him) became his guarantor. Then that man brought the amount (of gold) that he had promised, and the Prophet (peace and blessings be upon him) asked him: "Where did you get this gold from?" He said: From a mine. He (peace and blessings be upon him) said: "We have no need of it; there is no good in it." So the Messenger of Allah (peace and blessings be upon him) paid off his debt (on his own behalf). The chain of this hadith is sahih (authentic), but the two Shaykhs did not record it.