The Lord says that we are supposed to be the “salt of the earth” and “the light of the world” . In fact it’s a compliment we use today when we say someone is the “salt of the earth”. Yet we know there is nothing so inedible, so unhealthy as salt all by itself. During a famine you can’t eat it. In a drought, you don’t even dare go near it. Salt is useful only as an additive. It can bring out flavour & be a preservative when mixed with something else to prevent deterioration. We are the salt of the earth when we are an active part of our community, serving as a preservative.
The same is true with being the “light of the world.” Light by itself can blind us. Staring at the sun or a lightbulb can harm us. Light is useful when it enables us to see other things better. So we are the light of the world. We should light up consciences, minds and hearts.
How are we salt & light? Isaiah points out some ways that we have come to call the corporal works of mercy: feeding the hungry, sheltering the homeless, clothing the naked, giving drink to the thirsty, visiting those in prison, visiting the sick, burying the dead. Theses are the classical works of mercy The early church did them and the Church does them today. They are tangible ways of being salt & light. These are things that we do personally or that we support through the parish, the poor box, Catholic charities