There is no such thing as a private Christian. By their very nature, the true Christian must make a difference to society, because the Lord has told us we are like salt and light. Our presence must be detectable.
A lamp is lit to be put on the lamp stand, where it shines for everyone in the house.
Salt, as well as enhancing flavour, acts as an agent that prevents corruption (see Matthew 5:13-16).
True Christian influence in human society stands fast against all that corrodes and destroys what God has created as good (Genesis 1:31).
The light of Christian lives cannot compromise with the darkness in the world, but rather exposes it (Ephesians 5:11).
The mission of those who belong to Christ, in whom His Spirit dwells uniting us with His Father and our Father (John 20:17), is to preserve the truth that makes human beings free indeed (John 8:32-36).
It is this truth, revealed though Christ, that saves humanity from destruction. For all who are on the side of truth listen to His voice (John 18:37).
The Word of God is explicit about how we allow the Light of God to be authentically seen in the living of our lives.
"Thus says the Lord: Share your bread with the hungry, shelter the homeless poor, clothe the naked and do not turn from your own kin. Then will your light shine like the dawn and your wound be quickly healed over…. If you do away with the yoke, the clenched fist, the wicked word …. your light will rise in the darkness and your shadows become like noon (see Isaiah 58:7-10)."
Our own salvation - for salvation is healing - is inextricably connected with our love and compassion for others. Christian preaching is not just words.
The word 'preach' originates from the Latin 'praedicare', meaning 'to say in front of'.
The public expression of our faith is essentially the "message of the Cross" (I Corinthians 1:18), and the Cross of Jesus declares mercy.
The preaching of Christ crucified (I Corinthians 2:2) is not just sermons, important as they are.
It is action on the streets of our cities, towns and in our neighbourhoods.
To be light and salt is to be practically involved in "the work of mercy (II Corinthians 8:7)" for our poor, disadvantaged, marginalised and suffering brothers and sisters.