IMO....
The Gospel often doesn't get effectively shared because:
1. A lot of Christians don't know it. Even at THE most basic, central point of Jesus is the Savior. I find a LOT of Christians VERY fuzzy and confused even on the central, keystone point... a LOT of Christians blurring Law and Gospel, self and Christ... a LOT of Christians presenting a soteriology that actually is more akin to Judaism or Islam or some forms of Hinduism than Christianity. I'm NOT at all saying their faith is wrong (I'm sure their heart is 100% Christian) but how they understand this and thus communicate this is often VERY confused and something the Holy Spirit has a hard time using.
2. I think a lot of Christians are universalists. They don't believe in hell, they believe that everyone is God's child and so everyone will go to heaven. I read something from the owner of a small funeral home in the mid-west. He commented that in like 40 years, he has YET to hear a eulogy for even one person that did not say this person was in heaven. If everyone goes to heaven, then there's no need to evangelize.
3. I think a LOT of Christians are relativist. It's not WHAT you beleive but THAT you believe. A LOT of Christians think it doesn't matter what the OBJECT of faith is, just that faith is. "He was sincere in his faith that being a Republican would save him." "He belie"ved...." in WHAT seems not not matter. "What is truth?" to quote a Roman Governor. "There are many roads to heaven." "Who knows which religion is right?"
4. To just restate Lamm's point (but it's a good one!), a lot of evangelism is out of context. "People don't care what you know until they know that you care." Silly trying to convince of a loving God when you are unloving. Hard to show that Christ makes a difference when there is zero evidence of that in you.
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