Abu Hurairah (May Allah be pleased with him) reported:
The Messenger of Allah ﷺ said, "He who utters a hundred times in a day these words: 'La ilaha illallahu, wahdahu la sharika lahu, lahul-mulku wa lahul-hamdu, wa Huwa 'ala kulli sha'in Qadir (there is no true god except Allah. He is One and He has no partner with Him; His is the sovereignty and His is the praise, and He is Omnipotent),' he will have a reward equivalent to that for emancipating ten slaves, a hundred good deeds will be recorded to his credit, hundred of his sins will be blotted out from his scroll, and he will be safeguarded against the devil on that day till the evening; and no one will exceed him in doing more excellent good deeds except someone who has recited these words more often than him. And he who utters: 'Subhan-Allahi wa bihamdihi (Allah is free from imperfection and His is the praise)' one hundred times a day, his sins will be obliterated even if they are equal to the extent of the foam of the ocean."

[Al-Bukhari and Muslim].

وعنه أن رسول الله ﷺ قال: "من قال لا إله إلا الله وحده لا شريك له، له الملك، وله الحمد، وهو على كل شيء قدير، في يوم مائة مرة كانت له عدل عشر رقاب وكتبت له مائة حسنة، ومحيت عنه مائة سيئة، وكانت له حرزًا من الشيطان يومه ذلك حتى يمسي، ولم يأتِ أحد بأفضل مما جاء به إلا رجل عمل أكثر منه" وقال: "من قال سبحان الله وبحمده، في يوم مائة مرة حطت عنه خطاياه وإن كانت مثل زبد البحر" ((متفق عليه)).