I'm getting to the end of the Daily Dose of Greek series on Revelation and probably will have finished by the time this post is published. I noticed that in Revelation 22:13 (and also in Revelation 1:8) there are seven nominatives (excepting the speech tag in Revelation 1:8):
Revelation 22:13: ἐγὼ [εἰμι] τὸ ἄλφα καὶ τὸ ὦ, ὁ πρῶτος καὶ ὁ ἔσχατος, ἡ ἀρχὴ καὶ τὸ τέλος.
"I [am] the Alpha and the Omega, the first and the last, the beginning and the end."
Revelation 1:8: Ἐγώ εἰμι τὸ ἄλφα καὶ τὸ ὦ, λέγει κύριος ὁ θεός, ὁ ὢν καὶ ὁ ἦν καὶ ὁ ἐρχόμενος, ὁ παντοκράτωρ.
"I am the Alpha and the Omega," says the Lord God, "Who is and who was and who is to come, the Almighty."
Seven is a significant number in the Bible (the number of days in creation, the number of petitions in the Lord's Prayer, &c.), so I think it's significant that each of these verses has seven nominatives, but I'm not quite sure what that significance is.