Musnad Ahmad 836:1

Muhammad ibn Ja'far narrated to us, Shu'bah narrated to us, he said: I heard Ishaq ibn Suwayd, he said: I heard Mutarrif ibn Abdullah ibn al-Shikhkhir narrating from a man among the companions of the Prophet, may God bless him and grant him peace, who said: There was an amir in Kufa. He said: So he gave a sermon one day and said: "Verily, in the giving of this wealth there is a trial, and in the withholding of it there is a trial." And with that, the Messenger of God, may God bless him and grant him peace, stood in his sermon until he finished, then he descended.