Musnad Abu Ya'la al-Mawsili 118:56

Zuhayr ibn Harb narrated to us, Ya‘qub ibn Ibrahim narrated to us, my father narrated to us, from Salih, from Ibn Shihab: Anas ibn Malik narrated to me that the Messenger of Allah (may Allah bless him and grant him peace) said: "If the son of Adam had a valley of gold, he would love to have two valleys, and his mouth will not be filled except by dust, and Allah turns in forgiveness to whoever repents."