عن عَلِيٍّ رَضِيَ اللّهُ عَنْهُ: أَنَّ مُكَاتَبًا جَاءَهُ فَقَالَ: إِنِي عَجَزْتُ عَنْ كِتَابَتِي فَأَعِنِّي، قَالَ: أَلا أُعَلِّمُكَ كَلِمَاتٍ عَلَّمَنِيهِنَّ رَسُولُ اللّهِ صَلّى اللهُ عَلَيْهِ وسَلَّمَ، لَوْ كَانَ عَلَيْكَ مِثْلُ جَبَلٍ دَيْنًا أَدَّاهُ عَنْكَ؟ قُل: «اللَّهُمَّ اكْفِنِي بِحَلالِكَ عَنْ حَرَامِكَ، وَأَغْنِنِي بِفَضْلِكَ عَمَّنْ سِوَاكَ». رَوَاهُ التِّرْمِذِيُّ وقَالَ: حَدِيثٌ حَسَنٌ.

Ali (may Allah be pleased with him) reported that a mukatab (a slave under a contract of manumission) came to him and said: I am unable to fulfill my writ of manumission, so help me. He said: Shall I not teach you words that the Messenger of Allah (peace and blessings be upon him) taught me — such that, were there upon you a debt like a mountain, Allah would settle it for you? Say: "O Allah, suffice me with what You have made lawful in place of what You have made unlawful, and enrich me by Your bounty from all besides You." Reported by al-Tirmidhi, who said: a hasan (good) hadith.