The Messenger of Allah ﷺ said, "When one of you prostrates, let him keep his posture upright and not spread his forearms on the ground like a dog."
حدثنا علي بن محمد حدثنا وكيع عن الأعمش عن أبي سفيان
قال رسول الله ﷺ إذا سجد أحدكم فليعتدل ولا يفترش ذراعيه افتراش الكلب
[Sahih] Tirmidhi narrated it in the Book of Prayer, chapter on moderation in sujud, no. 275, from the hadith of Amash with this wording, and he said, hasan sahih, and Ibn Khuzayma graded it sahih, no. 644. Amash used the ambiguous form "an" in transmission, as noted previously at no. 178. His hadith has a corroborating witness agreed upon by Bukhari, no. 532, 822, and Muslim, no. 493, from the hadith of Anas with similar wording, see the following hadith.