I have finished my reading of 1 Peter, and let me tell you it was no walk in the park! Very challenging, but rewarding as well. So what book did I turn to next to read? None other than Revelation!
Already in my readings I have come across a strange grammatical (by strange, I mean a grammatical faux pas). I will reproduce the text of Rev 1:4-5a in Greek and English and then comment on the underlined parts:
4 Ἰωάννης ταῖς ἑπτὰ ἐκκλησίαις ταῖς ἐν τῇ Ἀσίᾳ· χάρις ὑμῖν καὶ εἰρήνη ἀπὸ ὁ ὢν καὶ ὁ ἦν καὶ ὁ ἐρχόμενος καὶ ἀπὸ τῶν ἑπτὰ πνευμάτων ἃ ἐνώπιον τοῦ θρόνου αὐτοῦ 5 καὶ ἀπὸ Ἰησοῦ Χριστοῦ, ὁ μάρτυς, ὁ πιστός, ὁ πρωτότοκος τῶν νεκρῶν καὶ ὁ ἄρχων τῶν βασιλέων τῆς γῆς.
4 John to the seven churches that are in Asia: Grace to you and peace, from Him who is and who was and who is to come, and from the seven Spirits who are before His throne, 5 and from Jesus Christ, the faithful witness, the firstborn of the dead, and the ruler of the kings of the earth.
What’s the problem, you ask, with the text? Well, in Greek the preposition ἀπὸ is followed by a genitive, but the above ἀπὸ is followed by the nominative ὁ ὢν καὶ ὁ ἦν καὶ ὁ ἐρχόμενος. Did John somehow forget the rules of the very language he was writing in? Obviously this is not the case because he gets it right immediately after when he says ἀπὸ τῶν ἑπτὰ πνευμάτων ἃ ἐνώπιον τοῦ θρόνου αὐτοῦ καὶ ἀπὸ Ἰησοῦ Χριστοῦ…(note the genitives proceeding the next two uses of ἀπὸ). So, John, why the grammatical mishap? Well, according Greg Beale, in his magisterial commentary on Revelation, this is an example of what is known as a “solecism.” A solecism is simply a mistake in grammar. But is John’s use of solecism purely accidental, or is there a rhetorical reason for such a use?
What can be adduces from Rev 1.4 is that it is an allusion back to the LXX text of Ex 3:14-15, where God declares himself to be “I am who I am (Ἐγώ εἰμι ὁ ὤν).” One answer to our question of why the solecism is that because John understands ὁ ὢν as the Divine Name for God, it is indeclinable.
Perhaps a better reason for John’s grammatical no-no is to highlight the allusion to the OT. This is what Beale argues in his commentary, and I would tend to agree with him on this point. Beale notes,
John’s solecisms are to be explained even more specifically as grammatically awkward because they are parts of OT verbal allusions carried over in their original syntactical forms as they stand in the OT.
He goes on to conclude,
[T]he overall purpose of these Septuagintalisms, stylistic Semitisms, and awkward OT allusions was probably to create a “biblical” effect in the hearer and, hence, to show the solidarity of the writing with the that of the OT; such stylistic employment of language likely expresses the author’s notion that the OT revelation through the church as the true Israel was penetrating uncompromisingly the pagan world in an irreversible manner.
What is clear is that John was taking extra special care to highlight the Divine Name of God. It would be unwise and unfair to think that John was somehow incompetent with the Greek language. I find it quite ingenious and creative to utilize a solecism to highlight an allusion to the OT. It helps his readers to pickup textual links that he wants to highlight as important.
 Greg Beale, Revelation (NIGTC), 103.