Prayer (Kitab Al-Salat): Details of Commencing Prayer

Dawud :: Book 3 : Hadith 902

Narrated Abdullah ibn Umar:

Sa'id ibn Ziyad ibn Subayh al-Hanafi said: I prayed by the side of Ibn Umar and I put my hands on my waist. When he finished his prayer, He said: This is a cross in prayer; the Apostle of Allah (peace_be_upon_him) used to forbid it.