45 "But because I tell the truth, you do not believe Me.
46 Which of you convicts Me of sin? And if I tell the truth, why do you not believe Me?
47 He who is of God hears God’s words; therefore you do not hear, because you are not of God."
Throughout this entire last part of Chapter 8, Jesus speaks of His sinlessness and His deity.
None of them could point to any sin in Jesus (v. 46), including lying, but they still wouldn't believe Him.
why do you not believe Me? (v. 46) Jesus answers His own question — they were not of God.
Jesus was God, so His truth was beyond anything they'd heard before — therefore, because He told them the truth, instead of what they'd expected to hear, they didn't believe Him.
The natural man cannot understand the things of God because he is without spiritual discernment.
Men prefer lies to the truth.
Psalm 58:3 — The wicked are estranged from the womb; they go astray as soon as they are born, speaking lies.
Psalm 62:4 — They only consult to cast him down from his high position; they delight in lies; they bless with their mouth, but they curse inwardly. Selah.
Isaiah 28:15 — Because you have said, “We have made a covenant with death, and with Sheol we are in agreement. When the overflowing scourge passes through, it will not come to us, for we have made lies our refuge, and under falsehood we have hidden ourselves.”
2 Timothy 3:7 — Always learning and never able to come to the knowledge of the truth.
2 Timothy 4:4 — And they will turn their ears away from the truth, and be turned aside to fables.