Salt and Light for a Christian is living the Kingdom Life in your most natural way in whatever arena that you are in. And what is the “kingdom life”? That’s the way of life that matches with the culture of heaven:
1) the worship of God
2) believing in Christ
3) honesty and integrity.
4 ) excellence in the way you do your work
5) having loving compassion for people
6) being selfless
7) having conviction
8) having faith
… All of these are kingdom values. So when a Christian lives out these kingdom values, he’s already being salt and light. It is not necessarily that he is like a pastor, always preaching sermons, sharing Scripture…
If you’re living out a lifestyle which matches the kingdom values of heaven, that lifestyle is very different from the fallen world we are in. That itself is high impact. Your life is already a living epistle. Already we are continuously, spontaneously, and effectively salt and light in our environment. People will be attracted to you… there’s just a glory about your lifestyle, about you, your character (not because of you but because it reflects God’s values)… Sooner or later, they will have to know why are you like that. That’s how you live your life in Christ: there is Jesus character. People are attracted to Jesus when Jesus is lived out in our life. That’s being salt and light.