Narrated Tawus: The Messenger of Allah (ﷺ) used to place his right hand on his left hand, then he folded them strictly on his chest in prayer
SahihSahihSahihBook 2 · Hadith 369
سنن أبي داود
Narrated Tawus: The Messenger of Allah (ﷺ) used to place his right hand on his left hand, then he folded them strictly on his chest in prayer