When we go into a crowd we are mixed with the crowd. The larger the crow is the harder it is for us to recognize our friend from afar unless that person has something that significantly stands out otherwise the person is submerged into the crowd. It happens for everyone because the crowd somehow limits our vision and seeing things close up that shortens our visibility. Christians need to wear the light of Christ before entering the world otherwise things of the world will swallow that person. Being swallowed is similar to losing one's identity. Once identity is changed the person is being changed from within. When a Christian loses his/her distinctiveness s/he loses his/her Christianity. Jesus used images such as salt and light to convey the message of identity. Salt doesn't only flavour the food but it also preserves the food from decay. As salt purifies, preserves, and penetrates, so do the disciples of Jesus. They need these qualities in their missionary field for identification. They purify, preserve, and penetrate a society for the kingdom of God. It happens in every society and there will be someone who gladly makes the missionary welcome while others strongly oppose and resist against the message of Christians' love and the symbols of love they carry with them. Keeping the Christians identity alive is vital important otherwise instead of being light for the world we allow the light of the world to cover us and we become one of them and the message of the Christians' love is being lost or being twisted to suit the occasion.
The other image is light of a lamp. Without proper lighting our vision is blurred and we get confused between fact and fiction. Works performed in the dark results in a poor outcome. Light also brings out the beauty of things such as a rainbow that lightens the sky; light shines over the surface of the ocean that enlightens heavy heart and helps us to relax and the light rays over morning dews brighten our day. In this sense light expresses both the beauty of the exterior world and the inner beauty of the hearts. Psalm 36,9 says that in His light we see the goodness of God and again psalm 119,105 it says God's words is a lamp that guides our steps.
God's grace fills our lives with spiritual light, joy, and peace and at the same time it dispels darkness out of our lives. The life of the disciples is to live in the light of God's salt and light that is truth and love. The light of Christ shines in the hearts of believers and enables them to see the beauty of the heavenly reality of God's kingdom. Jesus told his disciples that nothing can remain hidden or secret when we see with the light of God. We can try to hide things from others, from the world but we can't hide things from our hearts and from God. Everything is known to God because the light of Christ is stronger than darkness even though darkness tries to overcome the light but it will never surpass it.
Those who submit to God their lives will be salted with God's words and the light of Christ will shine on their path and their missionary work will not be stumbled because God's grace will accompany them. Their Christian identity is retained because God's love remains with them.