What is the gospel?
God is the perfectly good and holy Creator-King of everything. He made us to know Him, love Him and obey Him.
But even though we should all love God and obey Him, we have all rebelled against Him. We have all chosen to live life our own way rather than His good and perfect way. This is what the Bible calls sin.
God hates sin. Sin ruins the world. It breaks our friendship, our fellowship, with God. Sin is terrible and it must be punished by our holy Creator-King. The punishment for sin is death: separation from God and everything good. How great is the punishment for sin? It is so great that we can never earn God's forgiveness by what we do! It is so great that it goes on forever!
God would be perfectly right and just to let all people receive this forever punishment for sin. Yet in His great love and mercy, God chose to send His Son Jesus to take the punishment for sin. Jesus came to earth--the Son of God became a man! He lived a perfect life--without any sin--and offered it up as He suffered and died on the cross, as the perfect sacrifice for the sins of all who would ever turn from their sins and trust in Him as their own Savior. Then on the third day, God raised Jesus from the dead in victory over sin and death. God's people were saved once and for all time!
Now all who turn away from their sins and trust in Jesus as their Savior are forgiven their sins. God adopts them as His very own people, filling them with His Holy Spirit and giving them the delight of knowing Him as their Heavenly Father, Savior and King. He works in their hearts and prepares them for the delight of living with Him forever in heaven.