Sermon on the Mount (pt. 8)
Pondering the Principles of Proverbs
Guarding our heart requires that we be proactive with respect to those things that would tend to corrupt it—and those things are as many as the sands on the beach.
Therefore, it is NOT possible to take a preventative action against a certain type of enemy. We must have some sort of protection that will protect our heart against ANY kind of invasion.