Al-Bira' (b. 'Azib) reported: The Messenger of Allah (ﷺ) said. When you prostrate yourself, place the palms of your hands on the ground and raise your elbows.
Explanation & Benefits
Shaykh Maulana Abdul Aziz Alvi
Hadith Commentary: Benefits and Issues: In prayer, the elbows will be raised above the ground and will also be separated from the sides.
Source: Tuhfat al-Muslim: Commentary on Sahih Muslim, Page: 1104