Musnad Ahmad 3445

Tawoos narrated that he heard Ibn ‘Abbas say: When the Prophet (ﷺ) prayed tahajjud at night... And he narrated a du'a’ like that of Sufyan, except that he said: "... Your promise is true, and Your words are true, and the meeting with You is true.” And he said: "... what I do in secret and what I do openly, You are my God, there is no God but You.”