Hadith 1825
It is narrated from Sayyiduna Abu Qatadah (may Allah be pleased with him) that the Noble Prophet (peace and blessings be upon him) said: "When any one of you enters the mosque, he should perform two rak‘ahs of prayer."
Hadith 1826
The Imam, through his teacher Abdullah bin Hashim, narrates with the same chain as mentioned above. There is an addition in this: before sitting (he should perform two rak‘ahs).