This passage reminds us that personal belief is what saves. Your lineage, history, and heritage can give you some advantages, but it can’t save.
Jesus starts out by saying that He is the light of the world and brings life and illumination (12). The Pharisees call Him a liar, and Jesus points out that they don’t even know Him so they aren’t really in a position to judge Him (13-15)! Jesus’ says that His testimony is supported by the Father, and that the Father testifies of Him. Unfortunately they don’t have any idea who the Father is (16-20), and they will die in their sins because they don’t believe in Jesus (21-24). Jesus, however, knows the Father, because the Father is with Him. He does exactly what the Father wants and says what the Father says. His crucifixion will prove it, probably because of the resurrection that follows (25-30)!
Jesus continues by saying that His teaching will set them free if only they will believe. It’s not enough to be descendants of Abraham – they need to be set free from sin. They are really doing the deeds of their true father, the devil! If they truly were spiritual descendants of Abraham they would follow His teaching and believe in Him. In that way they would show that they belong to God and would never see death (31-51). The Pharisees think that He must be possessed. Everyone dies, even Abraham! Jesus says that Abraham saw His day coming and was glad. How could that be possible? Because Jesus is the fulfillment of the promise given to Abraham, the embodiment of the hope that God gave to Israel, and is God Himself (52-59). He is “I am!”
Romans 4:13-21 “For the promise to Abraham or to his descendants that he would inherit the world was not fulfilled through the law, but through the righteousness that comes by faith. For if they become heirs by the law, faith is empty and the promise is nullified.For the law brings wrath, because where there is no law there is no transgression either. For this reason it is by faith so that it may be by grace, with the result that the promise may be certain to all the descendants—not only to those who are under the law, but also to those who have the faith of Abraham, who is the father of us all (as it is written, ‘I have made you the father of many nations’). He is our father in the presence of God whom he believed—the God who makes the dead alive and summons the things that do not yet exist as though they already do. Against hope Abraham believed in hope with the result that he became the father of many nations according to the pronouncement, ‘so will your descendants be.’ Without being weak in faith, he considered his own body as dead (because he was about one hundred years old) and the deadness of Sarah’s womb. He did not waver in unbelief about the promise of God but was strengthened in faith, giving glory to God. He was fully convinced that what God promised he was also able to do.”