The Gospel of Jesus the Christ
All mankind are sinners, all are unrighteous and can not enter into the presence of God.
God showed mankind he is not able to live righteous even with guide lines.
So God being gracious and loving provided a way to become acceptable to him.
Accept his provision made by the atoning sacrifice Jesus the Christ made in mankind's behalf, to become God's adopted children and to receive his eternal existence in heaven not in in hell.
God's word says; God commended his love toward us, in that, while we were yet sinners, Christ died for us. ( this is the atoning sacrifice )
God also says in his word; That if thou will confess with thy mouth the Lord Jesus, and shalt believe in thine heart that God hath raised him from the dead, thou shalt be saved.
For with the heart man believeth unto righteousness; and with the mouth confession is made unto salvation.