Rev 1:8

1:8 the Alpha and the Omega. The first and last letters of the Greek alphabet. God is Alpha (Creator) and Omega (the One who ushers in the new heaven and new earth). He is Lord of all—past, present, and future—as suggested by “who is . . . is to come” (cf. 4:1–5:14 note). His sovereignty in creation guarantees the fulfillment of His purposes in re-creation (Rom. 8:18–25).

who is to come. In the future God will come to fulfill all His purposes (21:1–22:5).