The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1093

Tawus reported: We asked Ibn Abbas about sitting on one's buttocks (in prayer). (ala alqad mein) He said: It is sunnah. We said to him: We find it a sort of cruelty to the foot. Ibn 'Abbas said: It is the sunnah of your Apostle (may peace be upon him).