Depends on why you can't say Haile Selassie I and call God by his new name.
 And the Gentiles shall see thy righteousness, and all kings thy glory: and thou shalt be called by a new name, which the mouth of the LORD shall name.
 He that hath an ear, let him hear what the Spirit saith unto the churches; To him that overcometh will I give to eat of the hidden manna, and will give him a white stone, and in the stone a new name written, which no man knoweth saving he that receiveth it.
 Him that overcometh will I make a pillar in the temple of my God, and he shall go no more out: and I will write upon him the name of my God, and the name of the city of my God, which is new Jerusalem, which cometh down out of heaven from my God: and I will write upon him my new name.
 To him that overcometh will I grant to sit with me in my throne, even as I also overcame, and am set down with my Father in his throne.
 His eyes were as a flame of fire, and on his head were many crowns; and he had a name written, that no man knew, but he himself.
 And he was clothed with a vesture dipped in blood: and his name is called The Word of God.
 And he hath on his vesture and on his thigh a name written, KING OF KINGS, AND LORD OF LORDS.
 And they shall see his face; and his name shall be in their foreheads.
 And one of the elders saith unto me, Weep not: behold, the Lion of the tribe of Juda, the Root of David, hath prevailed to open the book, and to loose the seven seals thereof.
Definition - to prevail, overcome, endure, have power, be able
to be able, be able to gain or accomplish, be able to endure, be able to reach
to prevail, prevail over or against, overcome, be victor
to have ability, have strength