Prohibition of Placing the hands on the sides during As-Salat (ThePrayer)

Imam Al-Nawawi’s Riyad-us-Saliheen
Chapter 338
Prohibition of Placing the hands on the sides during As-Salat (The Prayer)

1752. Abu Hurairah (May Allah be pleased with him) said: We are prohibited from placing the hand on the side during As-Salat (the prayer).
[Al-Bukhari and Muslim].