The answer
It has so many interpretations, but the easiest is that, “it is the number of man”, (Revelation 13:18), because man was created on the sixth day. Through this God is saying, “My church do not be afraid from your enemies, because your enemies are only men”; 666 representing several powers trying to attack the church, which can be such things as Islam, Communism, and Atheism, but through the power of the Lord, the church will be victorious and shall overcome at last.
H.G. Bishop Moussa