The ruling on Qailulah (afternoon rest) -
Resting for a while after eating the afternoon meal is called Qailulah. Falling asleep is not necessary for this, and doing Qailulah is a Sunnah; it helps in the night worship. It is stated in a Hadith: "Do Qailulah, because Satan does not do Qailulah." (Kitab al-Nawazil / Vol: 15 / Page: 294)