Matthew 5:16 In the same way, let your light shine before others, so that they may see your good works and give glory to your Father who is in heaven.
Jesus spent most of the Sermon on the Mount telling His followers about the Kingdom of God and about who they are. He didn’t begin by telling them anything to do, He led up to that. The Sermon on the Mount is mostly descriptive, not prescriptive. First came the statements and the definitions, then came the mission.
In Matthew 5:14, notice that Jesus does not tell His followers to go be the light of the world. He tells us that we ARE the light of the world. We are the light of the world because God illuminated our hearts so that we’ll know Him. He then shines through us for others to see Him and know Him. Our testimonies as Christians are not always verbal. Sometimes it’s the good works we perform that ultimately lead people to see Jesus working in our lives. So what are “good works?”
There are obvious things that we can do for others to show them the character of God, like caring for the poor and loving the lost. There are other things that might not be as obvious, attitudes of the heart that manifest themselves in our actions. Sometimes pointing the way to God is as simple as doing things without complaining. One thing is for sure, others are watching. We are the light of the world whether we want to shine or not.
Salvation brings transformation and a Christian who has no good works to show for their transformation isn’t a very good witness. The Bible is very clear that works don’t save us from God’s wrath and reconcile us to Him. Only Jesus’ work on the cross can do that. It’s equally clear, though, that we’re supposed to do good works. We’re created with a purpose and given a mission, to point others to the Father by shining the light He’s put within us.