The gospel tells you who Jesus is and what He has done, and if you believe its message in your heart, and confess Him with your mouth, you will be saved (Romans 10:9).
Jesus—God's eternal Son—God manifest in the flesh—co-equal with the Father, being conceived by the Holy Ghost, was born of a woman, took upon Him a body prepared by the power of the Highest, and thus became a REAL MAN—very God and very man. Having lived a life of perfect obedience to God, He died on the cross, being made sin and a curse, and having exhausted the cup of Jehovah's righteous wrath, endured the sting of death, spoiled the grave of its victory, and destroyed him that had the power of death. He went up into heaven, and took His seat at the right hand of God.
Such is the infinite merit of His perfect sacrifice, that all who believe in Jesus are justified from all things—yea, stand in His acceptableness before God, and can never come into judgment, but are passed from death unto life.
This is the gospel!—the glad tidings of salvation which is preached in all the world.