"I am the Alpha and the Omega, the first and the last, the beginning and the end." Blessed are those who wash their robes so that they may have the right to the tree of life and that they may enter the city by the gates.
(Revelation 22:13-14 ESV)
"Our lives are bracketed, or, boundaried, not by the decisions and actions of Caesar, not by the rise and fall of Rome, nor by the rise and fall of the United States. Our lives are boundaried by him, ‘the first and the last.’ Whatever else happens in our history and whatever else happens in my history, Jesus is there as the first word and Jesus is there as the last word. And Jesus is here in the middle with the Word that gives us life.” (--Darrell W. Johnson, Discipleship On The Edge: An Expository Journey Through The Book of Revelation)
Painting above, Christ in the Hagia Sophia as "Pantokrator", which is Greek for "The Almighty (All-powerful) One".