Musnad Ahmad 594:8

'Affan narrated to us, Hammad ibn Salamah narrated to us, Zubayr Abu 'Abd al-Salam informed us, from Ayyub ibn 'Abd Allah ibn Mikraz—and he did not hear it from him, he said: "His companions narrated to me, and I have seen him"—from Wabisa al-Asadi. 'Affan said: "He narrated to me more than once, and he did not say: 'His companions narrated to me.'" He said: I came to the Messenger of Allah (peace and blessings of Allah be upon him), and I intended not to leave anything of righteousness (birr) or sin (ithm) without asking him about it. Around him was a group of Muslims asking him for religious verdicts, so I began stepping over them. They said: "Away with you, O Wabisa, from the Messenger of Allah (peace and blessings of Allah be upon him)." I said: "Let me be, so that I may draw near to him, for he is the most beloved of people to me that I should draw near to him." He said: "Let Wabisa be. Draw near, O Wabisa," twice or three times. He said: So I drew near to him until I sat before him. He said: "O Wabisa, shall I inform you, or will you ask me?" I said: "No, rather inform me." He said: "You have come to ask me about righteousness and sin." I said: "Yes." He gathered his fingertips and began poking them into my chest, saying: "O Wabisa, consult your heart, and consult your soul," three times. "Righteousness is that which the soul is tranquil with, and sin is that which wavers in the soul and fluctuates in the chest, even if the people have given you a verdict and given you a verdict."