In a sentence, the gospel is “the good news” that God saves sinners through the life, death, and resurrection of his son Jesus, who gave of his life on the cross as a ransom for sinners who respond by repentance and faith in the son of God.
In a few sentences, God, who is eternally holy and righteous, made man in his own image to know him, love him, and serve him. Soon after creation, man gave into the temptations of Satan and sinned by disobeying God’s commands. Consequently, Adam, and all of his offspring, because of Adam’s sin, were cut off from God. But God, because of his profound love for his creation, sent his son Jesus - fully God and fully man - into the world, where he lived a perfect life and died on a cross in the place of ruined sinners in total fulfillment of the law’s requirements and the consequences of sin. He rose from the dead three days later defeating sin’s greatest weapon, death itself, and demonstrating the wonderful reality that God’s wrath for sin had been satisfied. For all who repent of their sins and trust in him for salvation, God confers the righteousness of Christ and they are born into a new and eternal life with God.
Central components to the gospel: God, man, Christ, and response.
God: God is the creator of all things (Gen. 1:1). God is perfectly holy, just in all his ways, and worthy of the worship of his creation (1 John 1:5; Rev. 4:11).
Man: Man, though initially created good, has sinned and that sin has been passed on to all mankind (Gen. 1:26-28; Jer. 17:9; Rom. 3:23). The just punishment for man’s sin is physical and spiritual death through the righteous cup of God’s wrath (Rom. 6:23) which brings about eternal condemnation - hell.
Christ: Jesus, fully God and fully man, came to earth, lived a perfect life, obeyed the law completely, and willingly went to the cross in the place of man where he bore the full cup of God’s wrath for sin. He rose from the grave three days later, conquering death. To those whom God calls and who turn from their sins and trust in him for salvation, God credits Christ’s righteousness and gives to them eternal life (John 1:1; Rom. 1:1-4, Rom. 3:21-26; 1 Cor. 15:20-22; 2 Cor. 5:21; 1 Tim. 2:5; Heb. 7:26).
Response: All who wish to receive salvation must repent of their sins and, by faith, trust in Christ for salvation (Mark 1:15; Acts 20:21; Rom. 10:9-10). (Repentance simply means to turn from your sins.) Those who respond in faith enjoy the privileges of new life in Christ on earth through discipleship, church membership, and mutual love and care from other believers (2 Cor. 5:17; Eph. 2:19-22; 1 John 4:7) and in heaven through eternal life (John 10:27-28; Heb. 9:15).