The Messenger of Allah ﷺ said, "Whoever says 'Glory be to Allah and praise be to Him' one hundred times will have his sins forgiven, even if they were like the foam of the sea."
حدثنا نصر بن عبد الرحمن الكوفي حدثنا المحاربي عن مالك بن أنس عن سمي عن أبي صالح
أن رسول الله ﷺ قال من قال سبحان الله وبحمده مائة مرة غفرت له ذنوبه وإن كانت مثل زبد البحر
Agreed upon [by Bukhari and Muslim]. Bukhari narrated it in the Book of Supplications, chapter on the virtue of tasbih, no. 6405, and Muslim, no. 2691, from the hadith of Malik through this same chain, and it is found in Muwatta, 1/209, 210.