The Messenger of Allah (ﷺ) used to say in his tahajjud prayer(i.e. supererogatory prayer offered in or after the midnight) after he said the takbir; he then narrated the tradition to the same effect.
Sunan Abi Dawud Book 2, Hadith 382
← Previous Hadith When the Messenger of Allah (ﷺ) stood up for praying at midnight, he said: o Allah, be praise to Thee, Thou art the light of the heavens and the earth; and to Thee be praise; Thou are the maintainer of the heavens and the earth; and to Thee be praise, Thou art the heavens and the earth and what is between them; Thou art the truth, and Thy statement is truth; and Thy promise is the truth; and the visitation with Thee is true; and the Paradise is true and the Hell-fire is true and the Hour is true; O Allah, to Thee I turned my attention, and by Thee I disputed, and to Thee I brought forth my case, so forgive me my former and latter sins, and my secret and open sins, Thou art my deity, there is no deity but Thou.

Sunan Abi Dawud Book 2, Hadith 381 Next Hadith → I offered prayer behind the Messenger of Allah (ﷺ). Rifa'ah sneezed. The narrator Qutaybah did not mention the name Rifa'ah (but he said: I sneezed). So I said: Praise be to Allah, praise much, good and blessed therein, blessed thereupon, as our Lord likes and is pleased. When the Messenger of Allah (ﷺ) finished his prayer, he turned and said: Who was the speaker in prayer? He then narrated the rest of the tradition like that of Malik and completed it.

Sunan Abi Dawud Book 2, Hadith 383