As is commonly the situation, to properly grasp Jesus' profound lessons it is necessary to understand common realities of Jesus' world. Things that are very common place in our American society were not common in Jesus' life circumstances.
As an illustration, consider food. There was no refrigeration. That means there were no ice cubes, no chilled glasses, or no cooled tea, water, or colas. To be chilled in spring water was likely as cool as something got!
There were no freezers! Food could not be preserved by freezing! 'Freezer burn' was unknown! One did not come home from a day's work, go to a freezing compartment, put food in a microwave [which also did not exist], and have that food on a table ready to eat in about thirty minutes.
Preservation of food [including long term preservation of perishable foods] was limited to salting, drying, or a combination of both. If preservation by those methods did not occur, preservation did no occur! Even our 'old fashioned' methods of canning by pressure cooker did not exist.
Jesus used salt to teach a profound but simple lesson: Do no damage as you serve your purpose. In our text, Jesus said, "You are the salt of the earth; but if the salt has become tasteless, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled under foot by men."
Salt used in the right place for the correct, good purpose was and is incredibly powerful. Many with heart or blood pressure problems today must restrict their consumption of salt. For anyone liking the taste of food with salt [which is most people], that is a demanding, difficult adjustment. Most have little awareness of how much salt contributes to the taste of food until we eat food without salt. Salt continues to be powerful!
Salt correctly used is also a powerful preserver. Less than 75 years ago in America, family farms used salt as the means of preserving some types of fresh meat.
A principle of taxation [both ancient and modern]: tax things that are (a) high use and (b) commonly necessary. Since salt was such a substance in Jesus' day, it was taxed frequently. Those who made a living by transporting salt were taxed [often at border crossings]. Profit was lost!
Salt [sodium chloride] does not 'spoil.' A box of salt is never thrown away because it spoiled! However, in Jesus' day, those who transported/sold salt lost part of their profit each time it was taxed. Such people often "restored" profit by adding to their salt a cheaper substance that looked like salt. If a load of salt was so diluted by the cheaper substance, that 'salt' sold to the unsuspecting might not have enough sodium chloride in it to preserve. It had no power to preserve, not because the sodium chloride spoiled, but because the sodium chloride was too diluted to be effective.
Though the "salt" was not powerful enough to preserve, it was powerful enough to destroy. Thus private owners of weak salt had to be careful in disposing of the 'spoiled salt.' Just as the brine water from an ice cream freezer can kill vegetation, so could the 'spoiled salt.' While such salt was useless for 'good' purposes, it was powerful enough to be deadly. Thus it must be disposed in a place where it could do no harm.
Christians do not exist to be a danger to people, but to serve people. They are God's force for good in this world.
Today light is so common and cheap in the American society, we think little about light--until we are in true darkness with no light! In Jesus' day, darkness was everyone's reality after sundown. By our modern world's standards, the light available then was (a) inferior [dim] and (b) expensive.
Light was used to help people. The objective: place an available light on a pedestal so all in the room could see. The dim light provided an astounding contrast to the darkness. In Jesus' day many cities were on hill tops. After sunset or before sunrise, small lamps' collectively made a city obvious.
The intent of light was to be helpful! The intent WAS NOT to hide need from people's need!
The follower of Jesus is God's light to this world. The life one lives combined with one's helpfulness to others produces an inescapable, obvious benefit to others. The benefit is produced by the good works of Jesus' disciple.
Jesus' disciple does not do good works to advance self. People who do not follow Jesus see the obvious. It is God's influence in the disciple that motives him or her to do good. Thus they praised God, not the disciple. The source of the motivation is praised rather than the conduit of God's good influence. That is fine with Jesus' disciple! The more one follows Jesus to God the Father, the more unselfish one becomes. His or her motives are the motives of an unselfish disciple honoring God Who blesses him or her.
For Thought and Discussion
Link to Teacher's Guide
Lesson 9