Just wanted to share this comment on Scripture from a 1987 book I am reading. Front and back cover follow the quote, click to enlarge.
2. Light and Salt
Christ reminded the disciples of their twofold obligation: they were to be salt and light. The illustration of salt implies both the concept of a covenant people and a moral conscience in the culture at large. In the Old Testament salt was symbolic of a covenant (Num. 18:19). in ancient Greek and Arab societies, legal agreements were confirmed by eating bread dipped in salt. Jesus is suggesting that we who are his disciples are the salt of the earth—we are his covenant people. Salt was also utilized in ancient cultures for preserving and flavoring meat. Jesus seems to be implying that we are also a moral preservative and ethical conscience to ‘the society in which we live. As representatives of his righteous standards, we should be involved in preserving Judeo-Christian values as foundational for the health of the society in which we live.
Jesus also refers to us as the light of the world. Most commentators interpret this to mean that we have an evangelistic obligation to society. We are to shed the light of the gospel on the dark world around us. While this is certainly true, Jesus is also speaking of the light of our “good deeds” (v. 16). We are to be a moral conscience (salt), but at the same time we are to demonstrate that moral standard through our good deeds (light). In other words, we have no right to call for justice unless we are ourselves just in dealing with others….
- Richard John Neuhaus, Gen. Ed., The Bible, Politics, and Democracy (Grand Rapids, MI: William J. Eerdmans Publishing, 1987), 10-11; from chpt 1, “The Bible, Politics, and Democracy,” by Edward Dobson.