“Do not love the world, nor the things in the world. If anyone loves the world, the love of the Father is not in him.” 
– 1 John 2:15

In the New Testament, there are several symbols for the Kingdom of God. Jesus says it is like salt, like light, like water, like leaven, and like a key. What do these five things have in common? One thing: penetration. Salt penetrates meat to preserve it. Light penetrates darkness to illumine it. Water penetrates the soil to refresh it. Leaven penetrates dough to help it rise, and a key penetrates a lock to open it. As Christ-followers, we are not to let the world get into us. But God has placed us in the world for one very clear reason, and that is in order to penetrate our world with the Good News of the Gospel.