It is The Belief that His Imperial Majesty is The Fulfillment of both the old and new testaments found in the Holy Bible Is The Living God of the Bible as found in the book of Revelation, Isaiah, psalms, etc. The second coming of Jesus Christ in the glory of the father, Jah

From Revelation 3 12-13 we read that the Lord Jesus Christ will return with a new name written upon those that see H.I.M.

Revelation 3:12 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.

JAH RASTAFARI HAILE SELASSIE I

This is what is generally what is held by the Rastafari Faith. Although due to freedom granted to All in humanity, the views of peoples beliefs may differ also

I hope this has helped answer your question somewhat, although it is not a perfect answer it may give you some insight into Rastafari