Jesus was an expert at using examples to illustrate His point. During His Sermon on the Mount, Jesus used salt as an example to illustrate a point to His disciples. Jesus called His disciples the "salt of the earth" (Matthew 5:13). However, Jesus also gave a warning to His disciples.
Jesus warned His disciples that they, as the salt of the earth, should not lose their taste. In the world we live in, it is sometimes very easy to give in and do the popular thing. However, the popular thing is not always the right thing to do. In fact, much of the time it is the wrong thing to do. Once we come to Jesus, we should strive each and every day to draw closer to God, not to the world.
Something that is not salt cannot make unsalty salt salty again. Only salt can make something salty. We were once unsalty. However, Christ has made us, His disciples, the salt of the earth. Let's go out and make everything we touch salty, so to speak, and not let ourselves become unsalty salt by backsliding. Stay salty!