I set up a few ideas in this strip. One is the "confusion" of the father god and his son. Since I would be purposefully confusing/using the two throughout the strip -- having the father do some things and the son do other things, even though in the Bible all these things are simply done by "God" -- I made this strip as kind of a warning that this would be happening. Of course, this also points to the Christian idea that "the father and the son are one" (though you'll notice the Holy Ghost doesn't appear; my strip promotes binitarianism, not trinitarianism or unitarianism).
The next idea is the idea that this yellow Son of God character is eventually going to be Jesus. The larger joke is a commentary on John Milton and company who set up the son's/Jesus' role in nearly this way, from before the beginning of time (which is when the strip is taking place at this "moment"), except that instead of his role as the one sacrificed for/by humanity being certain, here it's 50/50. (I'll try not explain jokes too much in this commentary, but in this case, it seemed appropriate to show other things besides the joke itself.)
I didn't know at this point that I would be making the Son human within the book of Genesis. But it happens.