Musnad Ahmad
It was narrated from Muhammad Ibn al-Hanafiyyah that his father said: The Messenger of Allah (ﷺ) said: “The key to prayer is purification; entering it is takbeer and exiting it is tasleem.”
حَدَّثَنَا وَكِيعٌ، حَدَّثَنَا سُفْيَانُ، عَنْ عَبْدِ اللَّهِ بْنِ مُحَمَّدِ بْنِ عَقِيلٍ، عَنْ مُحَمَّدِ ابْنِ الْحَنَفِيَّةِ، عَنْ أَبِيهِ، قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مِفْتَاحُ الصَّلَاةِ الطُّهُورُ وَتَحْرِيمُهَا التَّكْبِيرُ وَتَحْلِيلُهَا التَّسْلِيمُ.
Grade: Sahih because of corroborating evidence; its isnad is Hasan] (Darussalam)
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