Why does Jesus say their real father is “the devil”
(John 8:43)?
The devil lied to Eve and caused sin and death to enter into the world.
“From the beginning he was a murderer and ... a
liar” (John 8:44), so those who want to murder and lie belong to
the devil.
What about telling a white lie?
Lie has no color.
To which of the people who rejected Him did Jesus cling?
Jesus implored crowds to believe in Him so that “He
who has ears to hear” (Matthew 13:9) can hear and believe. Jesus
clung to no one but God the Father and certainly not to anyone who
rejected Him. He preached the Gospel with full confidence that
“He who is of God” will hear
“God’s words” (John 8:46) and believe in Him,
while those who “are not of God” (John 8:46)
won't.
How do Jesus' words and example impact Gospel
preaching and witnessing today?
It frees us to focus on sharing the Gospel accurately and in its
entirety, including sin, hell, repentance, and leave who does and
doesn't believe entirely up to God.
What does that mean for the myriad modern techniques
and strategies aimed at getting unbelievers to say a prayer, which
supposedly will turn them into Christians?
They are unbiblical and often driven by the desire to fill the pews with
donors. And a Christian telling an unbeliever that he or she is saved is
worse than a doctor telling a man who has curable cancer that he is
cancer-free.