God created the first man and woman, Adam and Eve, by a definite creative act, after His own image. The historic fall from the original righteousness in which mankind was created is the source of all the evil in the world. The guilt of Adam's sin is reckoned to all his descendants, so that all men are conceived in a state of guilt, corruption, separation from God and condemnation to eternal death. This state is known as original sin, and from it proceeds all actual transgressions. Therefore, although completely responsible to God to perform what He has commanded, man is completely unable of himself to do any spiritual good, not even to repent of sin and believe on the Lord Jesus Christ.
From all eternity God has planned to save for Himself out of lost and fallen humanity an innumerable multitude, not because of any foreseen faith or merit on their part, but because of His mercy in Christ, who He appointed as the only Mediator, the prophet, priest and king of those whom the Father had given Him. All whom God has thus determined to save will certainly be called, justified and glorified.
According to the plan of God, Christ, the eternal second Person of the Godhead, united to Himself a real human nature through the womb of the Virgin Mary, becoming fully God and fully man in one Person, yet without sin. For the salvation of His people, He perfectly kept God's holy law, voluntarily suffered and died as a full and sufficient substitutionary sacrifice for them and thus making reconciliation to God for them. He was buried, rose bodily on the third day, ascended into heaven with the same body and sat down at the right hand of the Father. In heaven He now reigns over all things for the church and makes continual intercession for His people.