Abu Hurayrah said:
“The Messenger of Allah, peace and blessings of Allah be upon him, forbade putting the hands on the hips during prayer.” (Reported by Abu Dawood, no. 947; Saheeh al-Bukhaari, Kitaab al-‘Aml fi’l-Salaah, Baab al-Hadhr fi’l-Salaah).
Ziyaad ibn Subayh al-Hanafi said: “I prayed beside Ibn ‘Umar and I put my hand on my hip, but he struck my hand. When he had finished praying, he said, “This is crossing in prayer. The Messenger of Allah, peace and blessings of Allaah be upon him, used to forbid this.” (Recorded by Ahmad, 2/106 )
It was reported by Abu Hurayrah, may Allah be pleased with him, that the Prophet, peace and blessings of Allah be upon him, said that this posture is how the people of Hell rest; we seek refuge with Allah from that.