The book of Revelation does not teach that Jesus is God or even deal with Christianity. It's a book written in parables and figures of speech based on the customs and culture of Israel that deal with what will concern Israel in the future. The words “I am the Alpha and the Omega,’ says the Lord God” are not a teaching on the trinity or that we should believe or confess that Jesus is God. These words apply to God, not to Christ. The one “who is and who was and who is to come” is clearly identified in the context as God, not Jesus Christ. Revelation 1:4-5 reads: “Grace and peace to you from him who is, and who was, and who is to come, and from the seven spirits before his throne, and from Jesus Christ, who is the faithful witness, the firstborn from the dead, and the ruler of the kings of the earth.” The separation between “theone who is, was and is to come” and Jesus Christ can be clearly seen. The one “who is, and who was and who is to come” is God.
The phrase “the Alpha and the Omega” has caused many people to believe this verse refers to Christ. However, study of the occurrences of the phrase indicates that the title “Alpha and Omega” applies solely to God. Scholars are not completely sure what the phrase “the Alpha and the Omega” means. Lenski concludes “it is fruitless to search Jewish and pagan literature for the source of something that resembles this name Alpha and Omega. Nowhere is a person, to say nothing of a divine Person, called "Alpha and Omega" or in Hebrew, Aleph and Tau.
Although there is no evidence from the historical sources that anyone is named “the Alpha and Omega” Bullinger says that the phrase “is a Hebraism, in common use among the ancient Jewish Commentators to designate the whole of anything from the beginning to the end." That would make the expression the figure of speech polarmerismos, similar to "and there was evening, and there was morning” which stands for the whole day in Genesis 1. The best scholarly minds have concluded that the phrase has something to do with starting and finishing something, or the entirety of something. Norton writes that these words “denote the certain accomplishment of his purposes; that what he has begun he will carry on to its consummation.