Narrated Anas bin Malik:
The Prophet ﷺ said, "Be straight in the prostrations and none of you should put his forearms on the ground (in the prostration) like a dog."
حَدَّثَنَا مُحَمَّدُ بْنُ بَشَّارٍ، قَالَ حَدَّثَنَا مُحَمَّدُ بْنُ جَعْفَرٍ، قَالَ حَدَّثَنَا شُعْبَةُ، قَالَ سَمِعْتُ قَتَادَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ
" اعْتَدِلُوا فِي السُّجُودِ، وَلاَ يَبْسُطْ أَحَدُكُمْ ذِرَاعَيْهِ انْبِسَاطَ الْكَلْبِ ".
Sahih al-Bukhari, 822
Sahih al-Bukhari, Vol. 1, Book of Characteristics of Prayer, Hadith 785
Sahih al-Bukhari, Book of Characteristics of Prayer, Hadith 785