The story is based around a warrior prince named Arjuna having a conversation with the manifestation of God in the form of Krishna. Arjuna is confused because Krishna is explaining that giving up all earthly desire is the path to union with the divine. Yet Krishna is also imploring Arjuna to do his duty as a warrior prince and to fight in a battle to regain his kingdom. This is obviously a contradiction, since desiring to defeat his opponents and regain an earthly kingdom is in opposition to our traditional understanding of religious observance.
The idea these ancient authors were trying to communicate to us is that not everyone is going to be a monk. You need bricklayers, bakers, doctors and programmers. The trick is to realize that fully being a human, engaged in some activity, is equivalent to experiencing the divine. Nowadays we might feel more comfortable with the secular "flow" ideas, that mental state some experience when completely absorbed in their work.
So don't worry if you can't find the divine through ritual worship or through the exploration of spiritual wisdom. The divine is right there and possible for anyone to experience (if you believe the ancient authors of spiritual works like the Gita).
Bach is not the only such, but he is the master.
Could one write a 16-part invention? I doubt it; certainly I think it would be hard to conceive of playing it, but I can "look into" a complex invention as I hear it and see how it could subdivide and get an idea of where that could lead. Certainly anything beyond the physically representative is to me sublime, and still able to trigger synesthesthetic response.