This is a really, really basic translation but it goes something like: "Bind him to the sky, Amen. He absorbs and clings to the sky."
If your stuff is correct, "binding" could possibly mean "becoming one with" or something, since when you DT with Alastor you take on lightning powers and, of course, can fly.
Although...did the runes change when you were using Alastor or Ifrit (I can't remember off the top of my head)? Because if they didn't, then if there is supposedly a translation, it would have to be more broad, or it meant that Kamiya was lazy and didn't bother thinking to use a new set of runes for a different weapon
And even if Kamiya decided he wanted to use runes like this "just because they looked cool," it's possible that whatever programmers worked on the HUD and those glyph designs could have actually attempted to give them proper syntax.
This is all pretty neat, though. I've always been interested in glyphs and runes and stuff like that - it's part of what made me like DMC's contemporary fantasy setting.