Imagine a beautiful guitar, carefully crafted out of the finest mahogany and steel strings. Now imagine that fine instrument is never played. It is placed atop a bookshelf and never touched. It just collects dust. Tragic, right? What a thing is finds fulfillment when that thing does what it was made to do. Of what use is a guitar that makes no music?

What would be the point of turning on a lamp and then throwing a heavy blanket over it. It might still be a lamp, but it provides no light. (It only serves as a fire hazard!) Form and function are intimately connected.

In the Sermon on the Mount, Jesus teaches that the same is true of discipleship. He wants us to see that being a disciple and acting as a disciple are intimately connected. When God called us to faith, he declared that we were something new: light, salt, his children. Jesus now encourages us to be what God says we are, so that God might bless the world through us. As Jesus speaks to us, he means to mold our will to his own.