I Don't Think the Unbelieving Jews Would Believe Even if Jesus Came Down From the Cross at their Selfish Request

Some of the most arrogant words that any Christian may have read from the Bible says:

Matthew 27:40 

And saying, Thou that destroyest the temple, and buildest it in three days, save thyself. If thou be the Son of God, come down from the cross.

Mark 15:30 

Save thyself, and come down from the cross.

It should give anyone pause at the audacity people have. They already saw the signs that Jesus could heal the sick and raise the dead. They already saw Jesus verify His claims but they didn't want Him because of the hardness of their hearts. I thought that what if Jesus with the consent of the Father came down from the cross that moment. Would the unbelieving crowd believe?

My answer would still be no. Do you remember the Pharaoh during the Exodus? He already saw the signs. He already saw Moses' rod swallow up the others. He already saw unnatural signs and wonders hit Egypt. He already saw this and that but he still didn't believe. The same is applicable to the unbelieving Jews of that day.  If they wouldn't even believe Him when all the genuine miracles came, when He showed them the signs that He's the Son of God then what do you think will make them believe if He came down from the cross that instant? A lot of people already saw signs of John the Baptist's prophecies about the Messiah come to us but they still rejected Him. But the problem is not exclusive to the Jews but also to the non-Jews. 

The problem for the lost sinner is not a lack of evidence but a hardness of one's heart. We have atheists who still want to prove the Bible is just a book of fables. While some atheists got converted in their way to disprove the Bible but others are still stubborn to the very end. They see the evidence of the resurrection but they still don't want to believe. The reason? Here's what the Bible says when the atheist finally admits one's personal hatred for God:

Romans 1:21 

Because that, when they knew God, they glorified Him not as God, neither were thankful; but became vain in their imaginations, and their foolish heart was darkened.