In ancient times, salt was vital. The mineral had medicinal purposes as a natural antiseptic for cleaning wounds and killing bacteria. Salt was also used to preserve food, especially in hot climates where food spoils quickly, and for flavor as it is today.
In Scripture, Jesus warns his disciples about losing their saltiness. The salt used in that time would have been dug from the shores of the Dead Sea. An impure blend of salt deposits that formed a chalk-like substance which resembled real salt but didn’t have any of its properties. As time went by, the true salt would dissolve, leaving behind a useless residue fit only for throwing on the land.
There is something profoundly disappointing about something with the appearance of salt but none of its usefulness. This is why Jesus wants us to maintain our own salty distinctiveness so that we might continue to have an impact upon the wider world. This means being in right relationship with Him and following his commandments.
The Church is called to flavor every aspect of life and culture, countering the impact of sin and evil, making the world a better place for us to thrive.