The Originator is He of the heavens and the earth: and when He wills a thing to be, He but says unto it, "Be" -and it is.
Al-Baqra (The Cow) Verse 117
Allah's Apostle said, "If anyone of you enters a mosque, he should pray two Rakat before sitting."
Sahih Bukhari: Volume 1, Book 8, Number 435