Part 10 of Kingdom Life
Text: Matthew 5:13-16
You can listen to this sermon here.
“Let your light so shine before others, so that they may see your good works and give glory to your Father who is in heaven” (Matt. 5:16).
Is Christianity Good for the World?
Some non-Christians claim that Christianity has had a negative effect on the world (e.g, the Crusades). Of course, Christians will counter with all the good things Christians have done (e.g., started orphanages, hospitals, schools).
It’s true that many people who called themselves Christians have done terrible things. But these people have disregarded the teachings of Jesus. They are Christians in name but not in deed.
What You Are
What does Jesus expect his followers to be? Jesus gives two metaphors to describe his followers: (1) “You are the salt of the earth” (v. 13) and (2) “You are the light of the world” (v. 14). Jesus didn’t say, “You should be salt and light.” He said, “You are salt and light.”
Salt and light were very important to people in first century Palestine.  As “salt” and “light,” we are to have a good influence on those around us. Jesus says that when we let our light shine, people will “see [our] good works” (v. 16; cf. 1 Peter 2:12).
Citizens of God’s kingdom are to be people of good works.
A popular saying among Christians is “Preach the gospel, and if necessary, use words.”  But if we are to effectively share the gospel with others, we need to use both deeds and words. “It seems that ‘good works’ is a general expression to cover everything a Christian says and does because he is a Christian, every outward and visible manifestation of his Christian faith.” 
The Watching World
We are “the salt of the earth” and “the light of the world.” Jesus doesn’t want us to be isolated from the world. He prayed, “I do not ask that you take them out of the world…. As you sent me into the world, so I have sent them into the world” (John 17:15, 18).
We are not to be private Christians. Jesus says, “A city on a hill cannot be hidden” (v. 14). He wants the world to notice us. He wants people to see a difference in our lives. Salt is good for nothing if its saltiness is lost ; light is good for nothing if it is concealed.
God wants the world to see good works in our lives so that we might be witnesses of the power of the gospel.
If the world sees no difference in our lives, we will be “trampled under people’s feet” (v. 13). But if they see our good works, some will “give glory to [our] Father who is in heaven” (v. 16). 
“While Jesus is opposed to doing good works publicly for one’s own honor (6:1, “to be seen” by people), he exhorts his disciples to do those good works publicly for God’s honor (5:16; cf. 6:9).” 
We desire to bring glory to God because he has provided salvation for us through the cross.
 Salt had many uses, including preserving food.
 This saying is widely attributed to Francis of Assisi, but no published source has been located prior to the early 1990s.
 John R. W. Stott, The Message of the Sermon on the Mount, 61.
 Technically, it’s not possible for salt to lose its saltiness. We shouldn’t think that Jesus intended to give us a scientific explanation of the properties of salt.
 Of course, we shouldn’t always expect a positive response since the eighth beatitude speaks of persecution.
 Craig S. Keener, The Gospel of Matthew: A Socio-Rhetorical Commentary, 175.