The companion of the Messenger of Allah, Abu Qatadah (may Allah be pleased with him), narrates that I entered the mosque while the Messenger of Allah (peace be upon him) was sitting among the people, so I also sat down. The Messenger of Allah (peace be upon him) said: "What prevented you from praying two rak‘ahs before sitting down?" I replied, "O Messenger of Allah, I saw you sitting and the people were also sitting, so I sat as well." The Noble Prophet (peace be upon him) said: "When any one of you enters the mosque, he should not sit until he has prayed two rak‘ahs."