A man under a contract of manumission came to Ali and said, "I am unable to fulfill the terms of my contract, so help me."Ali said, "Shall I teach you words that the Messenger of Allah ﷺ taught me? If you had a debt the size of Mount Sir, Allah would settle it for you. Say, 'O Allah, suffice me with what You have made lawful so I have no need of what You have forbidden, and enrich me through Your bounty so I have no need of anyone besides You.'"
حدثنا عبد الله بن عبد الرحمن أخبرنا يحيى بن حسان حدثنا أبو معاوية عن عبد الرحمن بن إسحق عن سيار عن أبي وائل
أن مكاتبا جاءه فقال إني قد عجزت عن كتابتي فأعني قال ألا أعلمك كلمات علمنيهن رسول الله ﷺ لو كان عليك مثل جبل صير دينا أداه الله عنك قال قل اللهم اكفني بحلالك عن حرامك وأغنني بفضلك عمن سواك
[Its isnad is hasan]. Abdullah bin Ahmad narrated it in Zawaid al-Musnad, 1/153, from the hadith of Abu Muawiya al-Darir, transmitted the same way, and he stated explicitly that he heard it directly, according to Hakim, 1/538, and Dhahabi agreed with him.Abdul-Rahman is al-Qurashi, and Sayyar is Abu Hakam.