Sunan Ibn Majah
It was narrated that Jabir said: The Messenger of Allah (ﷺ) said: “When anyone of you prostrates let him be balanced in prostration, and not spread his arms as a dog does.”
حَدَّثَنَا عَلِيُّ بْنُ مُحَمَّدٍ، حَدَّثَنَا وَكِيعٌ، عَنِ الأَعْمَشِ، عَنْ أَبِي سُفْيَانَ، عَنْ جَابِرٍ، قَالَ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " إِذَا سَجَدَ أَحَدُكُمْ فَلْيَعْتَدِلْ، وَلاَ يَفْتَرِشْ ذِرَاعَيْهِ افْتِرَاشَ الْكَلْبِ " .
Grade: Sahih (Darussalam)
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