The word salary comes from an ancient word meaning “salt-money,” referring to a Roman soldier’s allowance for the purchase of salt. Someone who earns his pay is still said to be “worth his salt.” Salt has also been used to express promises and friendship between people. It was even considered by the Greeks to be divine. Today in many Arab cultures, if two men partake of salt together they are sworn to protect one another, even if they had previously been enemies. In some cultures, people throw salt over their shoulders when they make a promise.
This is what a salt covenant with God must be. A lifetime commitment to support a ministry that has dedicate time and other resources to bring lost souls unto the kingdom of Heaven. Your donation is that salt covenant.