8 I am Alpha and Omega, the beginning and the ending, saith the Lord, Which is, and Which was, and Which is to come, even the Almighty. Revelation 1:8 (1599 Geneva Bible)
The title for the Lord Jesus, “The Alpha and the Omega” is in Revelation 1:8, 11; 21:6; 22:13. Alpha is ἄλφα (alpha) and Omega is ὦ (ō), which are, of course, the first and last letters of the Greek alphabet. Our Lord used this to emphasize that He is beginning and ending and the first and the last (1:11). This concept declares at least three realities about the Lord Jesus.
First, it declares His self-existence. The concepts of the beginning and the ending and first and last are illustrated by the fact that the Hebrews, the Greeks and the Romans all used their alphabetic letters as numerals, which accounts for the ease with which alpha and omega also represent first and last. “First” does not mean “first created,” but rather He who already existed in “the beginning” (as in I Am) and who then brought all things into existence (John 1:1-3). The concept of “the beginning and the ending,” in fact, is rooted on Old Testament imagery (Isaiah 41:4; 44:6; 48:12-13).