In what ways are we to be the salt of the earth?

from the old testament

• Some scholars  see covenantal faithfulness in the background of the Matthew 5:13 passage. Some Old Testament passages refer to a “covenant of salt” (Numbers 18:19; 2 Chronicles 13:5). In those Old Testament passages, “salt” expressed faithfulness and perseverance (cf. Leviticus 2:13).

from the new testament

• The phrase, “salt of the earth,” is found in Matthew 5:13, which reads, “You are the salt of the earth, but if salt has lost its taste, how shall its saltiness be restored? It is no longer good for anything except to be thrown out and trampled under people’s feet.”
• Jesus refers to "taste," which implies that believers add “flavor” to the world. This use is similar to how Paul said, “Let your speech always be gracious, seasoned with salt, so that you may know how you ought to answer each person” (Colossians 4:6). A believer's speech and actions are to flavor the world with the knowledge of Christ, honoring God (1 Peter 2:12).
• The immediate context of taste and loss of taste encourages Christians to live out their salvation in “fear and trembling,” as Paul noted in Philippians 2:12. The context of that Philippians passage (2:12–18) is about being lights so the world sees believers' righteousness; this is the same idea as Matthew 5:14, which refers to believers as being “light” as well as “salt.”
• Others see salt as referring to judgment and purity, with Mark 9:49–50 being a supporting verse: “For everyone will be salted with fire. Salt is good, but if the salt has lost its saltiness, how will you make it salty again? Have salt in yourselves, and be at peace with one another.” Though the language is similar to Matthew 5:13, the Matthew passage doesn’t discuss judgment. Even the Mark passage is questionable as to whether it refers to believers as agents of judgment.

implications for today

Humanity has been in a free fall since Adam and Eve. Fortunately, God intervenes to both restrain the fall (Genesis 11:6–9) and to judge sinners (Genesis 6:5–7, 19:24–25). One way He restrains sin is by leaving believers on Earth. We are His “salt.”

As salt, we “flavor” the world by showing them what righteousness looks like. In a society that clamors for equality by dividing people into race, gender, and political identity, we show how God can unite people of different colors, genders, and politics through faith in Jesus.

We are also a preserving agent. While society is not perfect, many societies could be far worse. They are made better by the influence of the Bible and Bible-believing Christians. In a very real sense, Christians are God’s means for slowing humanity’s downward slide.

As “salt” in the world, we stand out. That can be uncomfortable. We may be tempted to hide our light (Matthew 5:15) or to be less “flavorful,” so no one notices us. Jesus warned against doing that because the more we look like the tasteless world, the more we are the world. While we can’t lose our salvation (John 10:28), we could become useless. Worse, that attitude may reveal that we were never really saved to begin with.

Be salt. You should taste, look, and sound different from the world. When you reflect Christ, you will be hated (John 15:18), but God works through His salt to have mercy on the world.