Singing is a potent life skill. Even the world knows that singing — true, heart-engaged singing — releases oxytocin into the body, a hormone that helps to alleviate anxiety and stress, while boosting your immune system, your mood, and serving as an ally in the fight against cancer. But even more importantly, singing releases a spiritual affection that breaks apart the cancer of our most ingrained sinful habits.

Singing is one of the most immediate actions we can take to stoke our God-centered affections, and yet we grow careless of this neglected spiritual discipline.

http://www.desiringgod.org/articles/sing-for-your-life