Musannaf Ibn Abi Shayba 21:259

Ubaydah ibn Humayd narrated to us, from Mansur, from Ata ibn Abi Marzuq, from Ka’b, who said: Dawud, peace be upon him, used to say: "O Allah, deliver me from every sin that descended tonight from the heaven to the earth," three times. And he would say: "O Allah, grant me a share in every good deed that descended tonight from the heaven to the earth."