Who is Jesus, and why did God send him?
John 8 is one of the clearest statements from Jesus about who he is, why he came, and how he can help us—if we believe. It unfolds as follows:
Jesus helps a sinner escape a death penalty, but he then speaks words she needs to hear to turn away from that kind of deadly sin. He then tells others that he is there to help them, too—to help them stop sinning lest they die in their sins. However, they do not believe he is the Son, the Christ, sent by God as the light of the world. Because of their unbelief, he warns them that they will die in their sins if they cannot receive his counsel with faith.
Some, however, do believe in him. To them, he says that they must hold to his teachings to truly be his disciples, so they can know the truth that will set them free from sin. They take offense at his implication that they are slaves, but he explains that by sinning, they are enslaved by their sin. They must remain in his teachings to be set free.
The dialogue concludes with Jesus affirming his credibility as a liberator—one greater even than Abraham, whom he spiritually precedes. Jesus is. He is in the fullest sense of existence. Therefore, the freedom he offers is eternal. No temporary liberation from sin counts for much, for temporary freedom is not what Jesus offers. He offers permanent liberty because he offers sonship with the Father, God—and that is forever.