TABARANI 5124:
from ʿAbdullāh b. Zayd b. Arqam from his father —
[Machine] On the authority of the Prophet ﷺ who said, "Whoever says after every prayer: 'Subhan Allāhi, Rabbil 'izzati 'ammā yasifūn, wa salāmun 'alal murasalin, wal hamdu lillāhi, Rabbil 'ālamīn', three times, he has fulfilled his obligation of what is best and most perfect in seeking reward."
الطبراني ٥١٢٤:
عن عبد الله بن زيد بن ارقم عن أبيه —
عَنِ النَّبِيِّ ﷺ قَالَ مَنْ قَالَ فِي دُبُرِ كُلِّ صَلَاةٍ سُبْحَانَ رَبِّكَ رَبِّ الْعِزَّةِ عَمَّا يَصِفُونَ وَسَلَامٌ عَلَى الْمُرْسَلِينَ وَالْحَمْدُ لِلَّهِ رَبِّ الْعَالَمِينَ ثَلَاثَ مَرَّاتٍ فَقَدِ اكْتَالَ بِالْجَرِيبِ الْأَوْفَى مِنَ الْأَجْرِ
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