Hadith on Salat: Seeking forgiveness, supplicating after prayer

Thawban reported: When the Messenger of Allah peace and blessings be upon him, finished his prayer, he would seek forgiveness from Allah three times and he would say, “O Allah, you are peace and from you is peace. Blessed are you, Majestic and Generous.

Source: Ṣaḥīḥ Muslim 591

Grade: Sahih (authentic) according to Muslim

عَنْ ثَوْبَانَ قَالَ كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِذَا انْصَرَفَ مِنْ صَلَاتِهِ اسْتَغْفَرَ ثَلَاثًا وَقَالَ اللَّهُمَّ أَنْتَ السَّلَامُ وَمِنْكَ السَّلَامُ تَبَارَكْتَ ذَا الْجَلَالِ وَالْإِكْرَامِ

591 صحيح مسلم كتاب المساجد ومواضع الصلاة باب استحباب الذكر بعد الصلاة وبيان صفته