Romans 10:14-15The logic is simple. Humanly speaking if no one shares the gospel then no one new will hear the gospel and no one will be able to believe the gospel. Therefore no one will become a Christian.
How, then, can they call on the one they have not believed in? And how can they believe in the one of whom they have not heard? And how can they hear without someone preaching to them? And how can anyone preach unless they are sent? As it is written: “How beautiful are the feet of those who bring good news!”
But if God is sovereign and he has chosen who he will save, it doesn't matter if we share the gospel does it?
To that I say go read Mark 7:9-13. We can't use one part of God's word to ignore another. We need to either accept the whole thing or ignore it.
Why then do we have to share the gospel?
- God tells us to. Who are we to ignore God's word? We aren't saved by what we do, but if we are saved then we need to obey God out of love and he tells us to share the gospel (Matthew 28:18-20).
- God chooses to use us. It is a blessing to be able to serve God and to be a part of his plan. If we refuse he can always raise up another like he did with Barak in Judges and with Moses in Exodus.
- God usually works through normal, not supernatural means. He can save people without anyone sharing the gospel with them, but he chooses to use his people to share his word. Isaiah 55:9: "As the heavens are higher than the earth, so are my [his] ways higher than your ways and [his] thoughts than your thoughts"
- If no one had shared the gospel then (humanly speaking) we wouldn't have become Christians. If that was the care you and I would still be wallowing in our sin and headed for God's wrath eternally. How can we be so selfish as to not offer God's salvation to others?
Don't get me wrong, this is something that I really struggle to do. I find it awkward and I chicken out most of the time. But that doesn't mean that I'm right to do so. God's been challenging me more and more on this and it is something that we all need to be doing - lovingly and graciously, but firmly and honestly as well.
I hope that was helpful!