In the Book of Revelation we find the verse, "I am the Alpha and the Omega, says the Lord God, who is and who was and who is to come, the Almighty" (Revelation 1:8). But what do you do with Revelation 22:13, which appears to be Jesus speaking (see verse 16), when he says, "I am the Alpha and the Omega, the first and the last, the beginning and the end"? Doesn't the command by Matthew's Jesus to, "Go therefore, and teach all nations, baptizing in the name of the Father, and the Son, and the Holy Spirit" (Matthew 28:19) show the existence of a triune deity.
Answer:
Despite the distinctiveness with which God and Jesus are regarded in the New Testament some Christians are under the misconception that God and Jesus form two-thirds of a triune deity. Partial responsibility for this error is due to the New Testament writers, who use a number of designations for Jesus, which are the same as those given to God in the Jewish Bible and in the New Testament. The resulting confusion as to whether certain New Testament passages refer to God or to Jesus helped to produce the belief in a triune god.
That Jesus, who is considered by the New Testament writers to be the link between God and creation, is called by some of the same designations that are applied to God is understandable. After all, the New Testament writers believed that God had conferred a tremendous amount of power upon this angelic being, so why not, as well, some of His names, which express certain facets of His being? But it is nevertheless clear that although the God of the New Testament interacts with the world He created solely through His "firstborn" (Colossians 1:15-17), the latter is still subservient to God. Because of the exalted yet subservient position in which they envision Jesus, the New Testament writers do not believe it compromises God's status to apply some of His names to Jesus (cf. Ephesians 1:21, Philippians 2:9, Hebrews 1:4). The use of common names is not intended to indicate that Jesus is of one substance with God.
Perhaps, if "the Alpha and the Omega" in Revelations 22:13 is actually a reference to Jesus it stems from the New Testament belief that the pre-incarnate Jesus was the first thing created by God. What is significant is not so much the use of this name as the fact that whenever the relationship between God and Jesus is treated, the New Testament writers always describe God as superior to Jesus.
In any case, in verse 12 the subject of verse 13 ("the Alpha and the Omega") says he is "coming quickly." Since Jesus has not come "quickly" this is either false prophecy or the text is not speaking about Jesus.