At the heart of the Christian faith is what the apostle Paul calls in Ephesians 6:19 the “mystery of the gospel.”
The gospel, at its core, is news, not advice. Advice is counsel we receive about something we must now go and do. On the other hand, news is a report we receive about something that has already been done apart from us and demands a response from us. Every other religion in the world offers advice, but only Christianity reports news. Christianity delivers the news of what God has done to reconcile sinful men and women to Himself, save a people for Himself from among all peoples of the earth, and heal everything in creation that has been shattered by sin. Although this mystery was hidden for ages, God revealed it in stunning high definition clarity through the incarnation, substitution, crucifixion, and resurrection of Jesus.