I have seen it happen. A person who is sincere and firm in his faith in Jesus by confession and outward appearances distances himself over time from the life-giving and sustaining gospel in Word and sacrament. At the same time, he begins to spend more time with unbelieving friends, families, coworkers, or classmates and to open himself to what they believe and how they live. Gradually, an erosion of faith and conviction occurs. First, he begins to tolerate their ungodly thinking and lifestyles. Then he defends them and accepts them. And finally, he himself practices what they do. In the end, he completely throws off his faith and life as a child of God and treats these blessings like shackles weighing him down and holding him prisoner. He isn’t even the same person anymore. What comes out of his mouth and what he does in his life are shocking. But the irony is often that person will say that nothing has changed in his spiritual life.
But something has changed: Jesus calls this “salt losing its saltiness.” Salt can be called salt, but if it is not salty, it’s not really salt anymore. When we lose what gives us our distinctiveness as Christians – our faith in Jesus – we cease to exert a beneficial spiritual influence, like unsalty salt ceases to season food or melt roadway ice.
But worse, Jesus warns us that continuing to harden our hearts against him in unrepentant rebellion against God eventually leads to a permanent loss of our identity as saved children of God and salt of the earth. “If the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled by men.”
So beware of the gradual erosion of your faith and a slow loss of your saltiness. Check your use of God’s Word and the sacraments, because only in the gospel is our identity as God’s children affirmed and renewed. Only there is repentance worked and strength given to be and stay the salt of the earth for the glory of our merciful Savior.