The practice of obedience to the words of Jesus improves faith in two ways. The first is that it increases one’s discernment of God’s will. As our Lord puts it, If anyone’s will is to do God’s will, he will know whether [my] teaching is from God…Or again, If you abide in my word…you will know the truth…

Discernment of God’s will is something completely different from theoretical knowledge of God. Discernment is the spiritual outcome of obedience, not of study – unless the studying itself is a practice of obedience. Everywhere in the Christian life the rule is the same: like produces like. The practice of obedience is an activity of faith, and its consequence is greater faith: deeper, wider, higher, of eternity. No amount of study, however prodigious, can increase discernment even one iota, unless that study is itself faithful.

A wise parent gives her child the keys to the car only once she is confident in the child’s ability to drive. Similarly God rewards discernment only to those who have proven they will make good use of it.

The second way the practice of obedience improves faith flows readily from our image of gravitational attraction. Each step towards Christ decreases the pull of everything in conflict with Christ. The manifestation of this movement in actual life is a growing indifference to the things of the world, most notably to the opinion of others.

Our Lord is quite clear about this. Think of the Beatitudes as rules for obedience to Christ, and notice how the list concludes: Do these things, and the world will hate you. What the world will hate is losing you, or more exactly, of losing your devotion, of losing your commitment, of losing your love. There is none more vindictive than the one no longer desired.

As we practice obedience to Christ, the things of the world begin to grow strangely dim, in the poetic image. All that is given priority over Christ fades first, then all that is not of Christ. And we must not shy from the truth here. We must not say, All the things and people I love most dearly will become even more dear to me. No, they probably will not. Unless you [are willing to] hate your father and mother… Many or even most of the things you have always found most compelling will begin to lose their interest and attractiveness to you, even the things the world tells you are loveliest. Even the things your own heart tells you are fair and true, or at least do no harm. The fact is, the discipline of obedience will reveal what is fair and true for you, and what isn’t. If you are not in Christ, you are a very poor judge of your own values. Inside of Christ, Christ will judge. That is the consuming fire, the fire that purifies one’s faith.