The more dominion you have over a field, the more you can discern it’s excellence.
Take an omelette, for instance. You have to eat lots of omelettes to discern a good omelette from a bad omelette. The more you observe, eat, and create, the greater expertise you have to make a judgement on quality omelettes.
Similarly, the more you immerse yourself in music, the greater ability you have to distinguish between beautiful music and ugly music, good music and bad music, true music and false music.
Whatever your interest (hymns, string quartets, folk music, film scores, etc.), saturate yourself with music from that genre. In time, you will learn how to perceive God honoring creative works.
Thoughts from Professor John Hodges’ lecture at the West Coast Christian Worldview Conference.

