At the heart of Christianity is the "gospel" — a word that simply means "good news".
We're inundated with news everyday. But good news—something which has the potential to benefit us personally—is far more rare. For some, hearing that a war is over is merely news. But for those with a loved one on the front lines, that announcement is good news.
The message of what God has done in the person of Jesus Christ is good news for all people everywhere.
When God first created our world, it was very good, with no heartache, no pain, and no death. God created humans in His image to know, love, and serve Him joyfully. Yet tragedy fell when those human beings distrusted and disobeyed God. As a result of their rebellion, a great divide occurred between God and humanity. Death entered the world as God's punishment upon this rebellion, and the earth itself fell under the disfavor of God. Instead of loving and finding satisfaction in the God who created them, humans would henceforth—and fruitlessly—love and seek satisfaction in other created things.
But God was not done with our world. In His remarkable mercy and love, God sent His divine Son to earth on a rescue mission. God's Son became a human being—born as Jesus of Nazareth at a specific time and point in history. Jesus lived a life of perfect trust in and obedience to God, only to be unjustly put to death by the authorities of His day. His death was not an unfortunate event or an accident, but a willing, sacrificial act to pay the penalty for the wrongs that others had done. He died to reverse the curse that had fallen upon the earth, and this was validated three days later as God raised Jesus from the dead.
Jesus will one day return to earth to renew the entire universe, to turn it back into a place with no heartache, no pain, and no death. God's people will dwell with Him in unending joy.
This is the good news of Jesus Christ, the announcement that God has acted in Jesus to redeem a broken world and ultimately to renew it to a place of goodness and joy, where all evil has been eradicated.
You have a part to play in this story. We all do. God's good news brings a choice to every one of us.
All of us are naturally inclined away from God, to distrust Him and to follow the desires of our own heart—to love and serve other "gods" (like money, sex, and power) instead of Him in our search for satisfaction, meaning, and joy. We can continue on in the way of our natural inclinations, with the ultimate result of being separated from God forever in hell—a place of unending remorse, grief, and pain, alienated from the One who is the source of all good.
Or we can embrace the good news of Jesus by repenting and believing. Repenting means turning away from these false gods that we pursue toward seeking and listening to God. Believing means trusting in Jesus to make us right with God, to teach us how to live, and to ultimately bring us home to live with God forever. It is this simple, genuine response of faith in Jesus Christ that God requires in order for all the "good" of the good news to be ours.