Musnad Ahmad 32:441

Bahz narrated to us, Ali ibn Mas'adah narrated to us, Qatadah narrated to us, from Anas, who said: The Messenger of Allah, peace and blessings of Allah be upon him, used to say: "Islam is public, and faith is in the heart." He said: Then he would point with his hand to his chest three times. He said: Then he would say: "Righteousness is here, righteousness is here."