NOTES for Mat 5:13-16
Jesus calls His disciples salt and light. These apparently incompatible things are the main thing by which they must differ from all other people. Salt by itself has no nutritional value, but it is precisely salt that gives flavor to a dish and makes it special. Living in the world, Christians fill it with a divine savor, which, however, does not belong to them, since the Lord has endowed them with it. But it is important not to lose the special gift received in baptism while living by the laws of this world, not to be absorbed into it, because to lose one's "saltiness" means to stop being a follower of Christ. Jesus also says of Himself that He is the "Light of the world." In this lies the amazing privilege of Christians: to be like their Teacher.
Like much of what the Gospel calls us to, this comparison of the disciples with light and salt is paradoxical. On the one hand, one must be insignificant salt, which does not exist for itself, and on the other hand, one must be like God.