Why is the Kaaba called House of God?

Muslims pray facing the Ka'bah, because that is the command of Allah and His Messenger. Who worshiped God. Only to the unity of the Ka'bah in worship of God. Ruled in a prayer facing Ka'bah. So just as fulfilling the commandments of God and the Apostles in which the science of jurisprudence facing Ka'bah is a requirement for something prayers.

Word of God: "So you faced in the direction of the Grand Mosque"

And the words of the Prophet to almusi'i shalatahu, who memburukan prayer with his saying: "And you faced the Qiblah (Ka'bah) and say the Takbir".

Ka'bah is called mecca called Bayt al-'Atieq and called Baitullah (house of God) with the meaning assigned to her home that many of God's grace, then idhofah temple of God is to glorify littasyrief. It is not necessarily that God lived there homeless. If Mr. Amat raising chickens, as well as other people are also raising chickens in one location, then the chicken coop Pak Amat does not mean that Pak Amat stay in the cage, but with a sense of enclosure allowed the birds are bred by Mr. Amat. So, do not play in the language of logic, and indeed in no logic at all, but left it to the development of society, with a sense of what that word would be directed, so he later established by the commission language. Well, so does the word Baitullah.