Hadith #4857 (Sunan Abi Dawud)
Book: General Behavior (Kitab Al-Adab)
Narrator(s): Abdah bin Sulaiman al-Klabi عبدة بن سليمان الكلابي أبو محمد الكوفي, Abu al-Aliyya al-Bara', Ziyad bin Feroz أبو العالية البراء زياد بن فيروز, Abu Burzah al-Aslami, Abu Hashim al-Rmany أبو هاشم الرماني, Hjaj bin Dinar حجاج بن دينار, Muhammad bin Hatm bin Yonus محمد بن حاتم بن يونس, Uthman bin Muhammad
Grade: Sahih

There are some expressions which a man utters three times when he gets up from an assembly he will be forgiven for what happened in the assembly; and no one utters them in an assembly held for a noble cause or for remembrance of Allah but that is stamped with them just as a document is stamped with a signet-ring. These expressions are: Glory be to Thee, O Allah, and I begin with praise of Thee, there is no god but thou; I ask Thy pardon, and return to Thee in repentance.

Source: https://parallelquran.com/hadith/sunan-abi-dawud-4857/