In short, the Gospel is the mind-blowing news that Jesus Christ died for sins and rose again, forever victorious over each and every enemy that stood between God and His chief creation: man. Now, because of this amazing work, there is nothing that separates those who believe from their Creator and all the joy that He promises. In order to fully understand what the Gospel is, however, it is important to understand why the Gospel is needed.
God's Magnificent Design
God decided in eternity past to begin creating the world with the intent to reveal His glory (Ps. 19:1). Every piece and part of creation was designed to unveil God's fame. God then designed mankind uniquely to be His image bearers (Gen. 1:26-28), and gave them the special privilege of reflecting His attributes (e.g. His love, kindness, gentleness, forgiveness, justice, etc.) in the world.
Mankind's Terrible Decision
Beginning with Adam, mankind quickly veered off of God's designed course (Gen. 3:1-24; Rom. 5:12) and chose the path of rebellion, sin, and death. Later, God created the nation Israel to be His chosen and treasured people so that they would be a blessing to the nations (Gen. 12:1-3; Deut. 7:6-11), but they too chose to rebel against God. The judges, the kings, and the prophets all failed to steer Israel back to God's intended course of revealing His glory.
God’s Amazing Solution
Jesus Christ, God in flesh, came to do what people are completely unable to do. Only through the death and resurrection of Jesus Christ are the redemption of man and the restoration of creation made possible. Jesus is our SAVIOR (He saved us from God’s eternal wrath); Jesus is our LORD (He is the master whom we love and serve); Jesus is our KING (He is the victorious king that is establishing His kingdom and overthrowing the kingdom of darkness).
The Gospel Summarized
Christians look to Jesus Christ alone for their salvation (Acts 4:12). They recognize that their sinfulness and rebellion has separated them from a perfect and holy God (Rom. 3:23). They believe that Jesus Christ, who was fully God, came as a man (Phil. 2:6-8), lived a perfect life (1 Pet. 2:22-23), offered His body as an unblemished sacrifice for our sins (Rom. 5:8-10), bore the full weight of the Father's wrath (1 John 4:8-10) and victoriously conquered death through His resurrection (1 Cor. 15:1-11).