(A), the first letter of the Greek alphabet. With Omega, the last letter, it is used in the Old Testament and in the New to express the eternity of God, as including both the beginning and the end. (Revelation 1:8,11; 21:6; 22:13; Isaiah 41:4; 44:6) hence these letters became a favorite symbol of the eternal divinity of our Lord, and were used for this purpose in connection with the cross, or the monogram of Christ (i.e. the first two letters, ch and r, of Christ's name in Greek). Both Greeks and Hebrews employed the letters of the alphabet as numerals.
Meaning of ALPHA in English
Smith's Bible English dictionary. Английский библейский словарь Смита. 2012