A simple version:
1. There is the music of Bach.
2. Therefore, God exists.
"You either see that one or you don't," half-jests Peter Kreeft.
A more sophisticated version of the argument will unpackage some of the intuitions many of us feel when connection music to reverence of God. The argument, which for now I will simply designate as *the* Aesthetic argument for God's existence.
Music is beautiful if it exhibits melody on top of repetition.
By analogy, nature is beautiful if it exhibits diversity among repetition.
The parity between the two cases is that there is some intelligent composer/designer who is able to translate their beautiful thought into something tangible. As great as Bach's music is, just think of how much great and more wondrous the entire cosmos is! We can, then, quite naturally infer that the designer of the cosmos is that much greater than Bach. Bach, of course, took his inspiration from this designer - the being we call "God."
I prefer the argument from order, since it's premises and conclusions are so clear and impossible to reject on pain of irrationality. There is obviously order in the world and, depending on your additional presuppositions, God is either order itself, or else the entity that causes order within the cosmos. However, why should we limit our mode of inquiry to what is logically and mathematically airtight? Arguments like the aesthetic argument simply tap into a different realm of inquiry that may be known with just as much certainty, just not in the same dry manner.
It's something to think about, at least.