It is surely, then, just and right to call God Father. Our natural fathers give us only what they, themselves, get from God. So even what they give us also comes from Him.
Before the time of Our Lord, the people in prayer did not call God Father. They feared Him more than they loved Him. When He spoke to them—as He did when He gave the Commandments to Moses—it was in thunder, lightning, and smoke. (Ex. 19). They looked upon God as a great and terrible king who would destroy them for their sins. He sent the deluge on account of sin, and He destroyed the wicked city of Sodom with fire from Heaven. (Gen. 7:19). They called Him Jehovah, and were afraid sometimes even to pronounce His name. But Our Lord taught that God, besides being a great and powerful king—the Ruler of the universe and Lord of all things—is also a kind and good Father, who wishes His children not to offend Him because they love Him rather than because they fear Him, and therefore He taught His disciples and all Christians to call God by the sweet name of Father.
“Who art in Heaven.” The Catechism says God is everywhere. Why then do we say, “Who art in Heaven,” as if He were no place else? We say so to remind us, first, that Heaven is our true home, and that this world is only a strange land in which we are staying for a while to do the work that God wishes us to do here, and then return to our own home; second, that in Heaven we shall see God face to face and as He is; third, that Heaven is the place where God will be for all eternity with the blessed.
“Hallowed” means made holy or sacred. Halloween is the name given to the evening before the feast of All Hallows or All Saints.