Is there a connection to the covenant of salt and salt in Mark 9?
It appears that there may be a link between the covenant of salt in the Old Testament and Jesus’ words about fire and salt in Mark 9:49-50. The covenant of salt is an expression based on the lasting nature of salt.
Salt was an essential ingredient in the sacrifices. The covenant and its sacrifices became known popularly as the covenant of salt because it was a forever covenant between God and Israel. But it was also because salt was used in many of the sacrifices in Israel.
The covenant of salt referred mainly to the Mosaic covenant and all of its laws. It was secondarily used of the covenant made with David in 2 Samuel 7. God promised to leave a king on the throne from the line of David forever. Salt became the image of “forever” because it never loses its saltiness unless combined with other things.
Jesus may be referencing this at first when he says that everyone of his disciples will endure the salting of fire. Fire can refer to the Holy Spirit but here it most likely refers to the suffering and trials that every disciple of Jesus will endure.
Just as there was salt and fire involved in the sacrifices in the Old Testament, disciples are offered to God as living sacrifices (Romans 12:1-2) and they endure the fires of life. Although Jesus has mentioned salt and fire together, he will then change the imagery in Mark 9:50).
“If salt loses its saltiness,” is probably a reference to the fact that salt in the Middle East and joined Jesus’ time was not the pure chemical. It was usually mixed with other things. These things that it was mixed with would make it lose its effectiveness.
Salt was used at the dinner table regularly. It usually was used when a person made a covenant with another person. The covenant of salt meant that there was a friendship that developed through that covenant between the two human parties.
They would commonly say, “There is salt and bread between us.” Or they would say, “he has eaten from my salt at my table.” The salt became a sign of the covenant that was made.
“Have salt among yourselves, and be at peace with one another.” This last sentence that Jesus spoke on the subject probably refers to living at peace with one another. To have salt between ourselves means to make the covenant of peace.