Riyad as-Salihin: The Book of the Remembrance of Allah – Hadith No. 743 — Mu’adh (May Allah be pleased with him) reported: The Messenger of Allah (ﷺ)… (Hadith No. 743)

Mu'adh (May Allah be pleased with him) reported: The Messenger of Allah (ﷺ) took hold of my hand and said, "O Mu'adh! By Allah I love you, so I advise you to never forget to recite after every prayer: "Allahumma a'inni ala dhikrika, wa shukrika, wa husni 'ibadatika (O Allah, help me remember You, to be grateful to You, and to worship You in an excellent manner).".

Explanation:

Reference: Riyad as-Salihin, The Book of the Remembrance of Allah, Hadith No. 743