Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) narrates: We used to say among ourselves that the Prophet (peace and blessings be upon him) had made seventy covenants specially with Sayyiduna Ali (may Allah be pleased with him), which he did not make with anyone else. (Making a covenant here may also mean giving particular instructions.)
Al-Tabarani recorded it in al-Mu'jam al-Saghir, and its chain contains narrators whom I do not know.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب المناقب / 14664
Hadith Gradingمحدثین:إسنادہ ضعیف
Hadith Takhrij«اخرجه الطبراني فى المعجم الصغير (956)»