Charles Ellicott Commentary Revelation 1:8

"I am the Alpha and the Omega, saith the Lord God, who is and who was and who is to come, the Almighty." — Revelation 1:8 (ASV)

The beginning and the ending.—These words are of doubtful authority; they are in all probability taken from Revelation 22:13, and interpolated here. The description of the verse applies, with little doubt, to our Lord, and the words are a strong declaration of His divinity.

The Almighty.—The word rendered this way is, with one exception (2 Corinthians 6:18), unique to this book in the New Testament.