BAYHAQI 2261:
from Ibn al-Ḥanafiyyah —
[Machine] Narrated by Ali, he said that the Prophet ﷺ said, "The key to prayer is purification, the initiation of prayer is the takbeer (saying Allahu Akbar), and the conclusion of prayer is the tasleem (saying salaam)." Imam Shafi'i (may Allah have mercy on him) said this was also narrated from Ibn Mas'ood.
البيهقي ٢٢٦١:
عن ابن الحنفيه —
عَنْ عَلِيٍّ رَفَعَهُ إِلَى النَّبِيِّ ﷺ قَالَ مِفْتَاحُ الصَّلَاةِ الطَّهُورُ وَإِحْرَامُهَا التَّكْبِيرُ وَإِحْلَالُهَا التَّسْلِيمُ قَالَ الشَّافِعِيُّ رَحْمَةُ اللهِ عَلَيْهِ فِي الْقَدِيمِ وَكَذَلِكَ رُوِيَ عَنِ ابْنِ مَسْعُودٍ
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