Salt is both a seasoning and a preservative. We sprinkle spiritual salt on our anger to turn it into meekness; on our bitterness to change it into forgiveness; on our doubts to change them into faith; on our inclination to gossip so we may change this malignant habit into acceptance of others; on our restlessness so we may become content with life. The seasoning and preservative is found in God's Word, for it is here and here only that we find the code of conduct for our lives.
Jesus told His disciples and us in His Sermon on the Mount that His people are savors of others. Salt, to be effective, works quietly and unobtrusively. We go out into the world and act and speak with grace seasoned with the salt of compassion and encouragement. A wise word is spoken in reason as well as in season. Jesus also lamented salt-less salt: "It is no longer good for anything..." (Matthew 5:13). How it must grieve Him when we don't live up to the potential and the nobility He has given us. "How the gold has lost its luster, the fine gold become dull!" (Lamentations 4:1).
Therold gives an excellent description of one who has lost the flavor of Christianity: "The bane of the Church of God, the dishonor of Christ, the laughingstock of the world, is in that far too numerous body of half alive Christians who choose their own cross, and shape their own standard, and regulate their own sacrifices, and measure their own devotions; whose sacrifices do not deprive them of a single comfort from one year's end to another, and whose devotions never make their dull hearts burn with the love of Christ."