Musannaf Ibn Abi Shayba 28:1099

Abu al-Ahwas narrated to us, from Simak, from Ikrimah, from Ibn Abbas, that the Prophet (peace and blessings of Allah be upon him), when he intended to return from his journey, would say: "Returning, repenting, to our Lord praising." And when he entered upon his family, he would say: "Repentance, repentance, to our Lord, a return that leaves no sin upon us."