Musannaf Ibn Abi Shayba 33:40

Qabisah narrated to us, from Sufyan, from al-Ala’ ibn al-Musayyab, from a man, from Mujahid, who said: David said, "O my Lord, my life has become long, my age has advanced, and my strength has weakened." So Allah revealed to him, "O David, glad tidings to the one whose life is long and whose deeds are good."