Dr. Fruchtenbaum, what do you think Jesus meant by this? “Everyone will be salted with fire” (Mark 9:49). “Salt is good but if loses its saltiness, how can you make it salty again? Have salt in yourselves, and be at peace with each other” (Mark 9:50). Some commentators said salt is suffering, but is verse 50 referring to something else?
You are correct, that I do not think that salt is being used for suffering in the context of Mark 9:49-50. In light of this context it is more helpful to connect it with what Jesus taught in Matthew 5 that believers are the salt of the earth.
Salt was used for two purposes: as a preservative and as a seasoning. On one hand as a preservative, it is the existence of the remnant that keeps the nation as a whole alive and from being totally destroyed. As a seasoning, it makes life worth living since we are able to fellowship with each other.
Thus Jesus encourages believers here to “have salt in yourselves” which means to serve as a preservative for the world and also to serve as a seasoning. As a seasoning, salt is good if it does not lose its saltiness but once the saltiness is lost, it is no longer able to serve as a seasoning. Thus when a believer falls into sin he is out of fellowship with the Lord and he is also out of fellowship with fellow believers and therefore, he is not at peace with them. But if he is obedient, then he can be at peace with God and with fellow believers. So Jesus goes on to say “have salt in yourselves and be at peace with one another”. So again, the issue here is not suffering but rather playing the role of a preservative and a seasoning that makes life among believers worth living.