Why did Jesus refer to humans as salt?

Salt provides essence and taste to food; no one prefers having bland food, hence the saying "take it with a pinch of salt". In this sense Jesus says that people are the essence of the earth, the planet, it is no longer good for anything, except to be thrown out and trampled underfoot.

The planet's survival is based on the mere existence of humans. Humans are like salt they provide the flavour to the food, too much or too little can spoil the taste of the food (earth). They, humans, like salt have the power to turn earth into something better or worse depending upon their essence (flavour).

The essence of salt is its flavour, the essence of a human is his conscience, most commonly referred to as a person's soul. If salt (humans) loses i's flavour (essence), it's of no use to anyone or anything. And as a matter of common sense something that is not useful to anyone is disposed off without thought or second consideration, - I mean would you keep something that you find useless? Hence the words "It is no longer good for anything, except to be thrown out and trampled underfoot."

I hope this a good answer for the words that Jesus used-

As with reference to the verse Matthew 5:13:

13 “You are the salt of the earth. But if the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled underfoot.

Thank you for your patience

Why did Jesus refer to humans as salt?

There may be possibly several reasons for this.

• Salt helps preserve food. Blessed is he who preserves the faith until the end.
• The faith in Christ is like a valuable pearl of great price. So too was salt in antiquity: it’s value was compared to gold.
• Salt adds flavour to food. Men who believe in God’s word recognize that man can not live by bread alone, but by every word that comes from the mouth of God.

First of all, before going into the question at hand, I would like to recount a little story about a someone giving a homily on this topic in French and he majorly messed up to the congregation by saying you the dirt soil of the earth! Vous êtes la sale terre! in French that could be translated as: You are the dirty soil of the earth! He meant to say: Vous êtes le sel de la terre! You are the salt of the earth. That a huge difference.

Roman soldiers were paid in salt!

Near Lausanne, in the foothills of the Alps, there are several centuries-old salt mines which are still operational today. In Roman times, and throughout the Middle Ages, salt was a valuable commodity, also referred to as "white gold." This high demand for salt was due to its important use in preserving food, especially meat and fish.

Being so valuable, soldiers in the Roman army were sometimes paid with salt instead of money. Their monthly allowance was called "salarium" ("sal" being the Latin word for salt). This Latin root can be recognized in the French word "salaire" — and it eventually made it into the English language as the word "salary."

Language is something we take for granted; we use it every day and could not live without it in today's world. However, as the example with the word "salary" shows, languages are not static but, rather, evolve. While the differences between American and British English are manageable, for example, reading Shakespeare in its original form poses some challenges — and reading the original Beowulf is almost impossible. -[From Salt To Salary: Linguists Take A Page From Science

At this time in history, not only was salt used to preserve food, but it was so valuable that that Roman Army was even paid their wages in salt. That gives a whole new meaning that someone is worth his weight in salt (not gold).

Salt in food

Salt is present in most foods, but in naturally occurring foodstuffs such as meats, vegetables and fruit, it is present in very small quantities. It is often added to processed foods (such as canned foods and especially salted foods, pickled foods, and snack foods or other convenience foods), where it functions as both a preservative and a flavoring. Dairy salt is used in the preparation of butter and cheese products. As a flavoring, salt enhances the taste of other foods by suppressing the bitterness of those foods making them more palatable and relatively sweeter.

Before the advent of electrically powered refrigeration, salting was one of the main methods of food preservation. Thus, herring contains 67 mg sodium per 100 g, while kipper, its preserved form, contains 990 mg. Similarly, pork typically contains 63 mg while bacon contains 1,480 mg, and potatoes contain 7 mg but potato crisps 800 mg per 100 g. Salt is also used in cooking, such as with salt crusts. The main sources of salt in the Western diet, apart from direct use of sodium chloride, are bread and cereal products, meat products and milk and dairy products.

In many East Asian cultures, salt is not traditionally used as a condiment. In its place, condiments such as soy sauce, fish sauce and oyster sauce tend to have a high sodium content and fill a similar role to table salt in western cultures. They are most often used for cooking rather than as table condiments.

In religion

In the Hebrew Bible, there are thirty-five verses which mention salt. One of these mentions Lot's wife, who was turned into a pillar of salt when she looked back at the cities of Sodom and Gomorrah (Genesis 19:26) as they were destroyed. When the judge Abimelech destroyed the city of Shechem, he is said to have "sown salt on it," probably as a curse on anyone who would re-inhabit it (Judges 9:45). The Book of Job contains the first mention of salt as a condiment. "Can that which is unsavoury be eaten without salt? or is there any taste in the white of an egg?" (Job 6:6). In the New Testament, six verses mention salt. In the Sermon on the Mount, Jesus referred to his followers as the "salt of the earth". The apostle Paul also encouraged Christians to "let your conversation be always full of grace, seasoned with salt" (Colossians 4:6). Salt is mandatory in the rite of the Tridentine Mass. Salt is used in the third item (which includes an Exorcism) of the Celtic Consecration (cf. Gallican Rite) that is employed in the consecration of a church. Salt may be added to the water "where it is customary" in the Roman Catholic rite of Holy water.

In Judaism, it is recommended to have either a salty bread or to add salt to the bread if this bread is unsalted when doing Kiddush for Shabbat. It is customary to spread some salt over the bread or to dip the bread in a little salt when passing the bread around the table after the Kiddush. To preserve the covenant between their people and God, Jews dip the Sabbath bread in salt. - Salt

Now if salt goes bad, it is worthless, both financially, as a preservative and as a addictive to make food taste better.

Thus we can see why Our Lord spoke thus about salt in reference to the verse Matthew 5:13:

13 “You are the salt of the earth. But if the salt loses its saltiness, how can it be made salty again? It is no longer good for anything, except to be thrown out and trampled underfoot.

Jesus desires his disciples to be the real salt of the earth and worth their weight in salt, so to speak! They must preserve the faith and share the Good News with all of mankind.

He did not refer to "people" as in "all humans", but to those who do his will, ie, "good Christians"

And like other answers suggest, salt has a numbers of great properties:

• preservative [something we could not live without pretty much]
• taste enhancer [something that brings out the taste already in the food]

ie, so people of God are (or supposed to be :) those who preserve the good of this world, and give it its intended "taste" / happiness.

I do not see the preservative characteristic of salt fitting very well. Do we preserve the "purity" and "good of this world" or is this world without purity and good? Are we able to preserve anything or is it only the blood of Christ that preserves by bringing mankind from death to life?

I hold that we, as followers of Christ, are flavor enhancers bringing out the "God flavors" of life. (Eugene Peterson) By our words and actions, our attitudes and perspective, our good deeds, we can bring out the evidence of God's hand in even difficult situations.

Salt brings out the best, light brings comfort, reveals faults and guides the way. Together, they point to God's glory and abundant life in Christ alone.

Salt fulfills a very specific purpose which other more valuable things do not. One significant thing salt is used for is as a preservative. In the age before refrigeration, this was very important.

To apply this symbolically to followers of Christ, it would seem that they serve to preserve the purity of the world. As it was in the days of Noah, there is a bent in mankind toward impurity. True followers of Christ, the Bible teaches, are called to be pure. Thus, the impact of Christians in the world is to hold the line, so to speak--to bring a standard of righteousness and purity into the world that is supposed to bring restraint to the progress of evil.

Also, salt was used metaphorically in rabbinic literature of the day to refer to wisdom. this would actually fit quite well with the Old Testament where it says "the fear of the Lord is the beginning of wisdom." (Proverbs 8:13) So, calling followers of Jesus or fearers of God "the salt of the earth" is quite appropriate.