Abbas bin Sahl bin Sa'd narrates: Sayyiduna Sahl (may Allah be pleased with him) came to al-Hajjaj while he was reclining on his hand. Sayyiduna Sahl (may Allah be pleased with him) said to him: "The Prophet (peace and blessings be upon him) said concerning the Ansar: 'Do good to the good among them and overlook the wrongdoer among them.'" Al-Hajjaj asked: "Who will bear witness for you?" He said: "These two who are sitting at your sides, Abdullah bin Ja'far and Ibrahim bin Muhammad bin Hatib." The two of them replied: "Yes! (That is, it is so.)"
Imam al-Tabarani recorded this narration. Its chain contains Abd al-Muhaymin bin Abbas bin Sahl, who is da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب المناقب / 16506