Someone has pictured legalism and libertinism as two parallel streams that run between earth and heaven. The stream of legalism is clear, sparkling, and pure; but its waters run so deep and furiously that no one can enter it without being drowned or smashed on the rocks of its harsh demands. The stream of libertinism, by contrast, is relatively quiet and still, and crossing it seems easy and attractive. But its waters are so contaminated with poisons and pollutants that to try to cross it is also certain death. Both streams are uncrossable and deadly, one because of impossible moral and spiritual demands, the other because of moral and spiritual filth.
But spanning those two deadly streams is the bridge of the gospel of Jesus Christ, the only passage from earth to heaven. The two streams lead to death because they are man’s ways. The gospel leads to life because it is God’s way.