I love this photo. Everything, from the way they're holding hands, to the seeming obliviousness to the rain, to the way their backs are to the viewer as if you're watching them walk out of Eden. Even the murky reflections! The only thing that spoils it for me is Adam's tanline. It's just a bit too jarring. Other than that though, everything is great!
Just a few things I would suggest; - The road. If we're talking about the Adam and Eve here, then I'm pretty sure there wasn't a paved road for them to walk on. - I'm not entirely sure about this, but is that a tattoo on the back of Adam's neck? Based on the models' state of (un)dress here, I would assume this is supposed to take place before Eve ate the Fruit, so it doesn't make sense Adam would have a tattoo when he's supposed to be the epitome of a Man of God at this point. - This ties in with the tattoo; the tan line on Adam implies that he wears clothes (a lot). Adam and Eve were naked, therefore he would have a pretty even tan.
Other than that, I'd say this is a really great shot
Maybe it's just me, but I took the title and photo combo as a cute modern take rather than something meant to be a literal interpretation of the Bible, but you made interesting observations nonetheless.