Q. I have never understood John 12:39-40 and other verses that speak of the same thing. Why would God blind people so they wouldn’t understand, or harden their hearts? This verse says “so they would not see…or understand…and be converted..” Why?
A. We have to understand that we determine the course of our lives by the choices we make. We demonstrate our wishes through the persistence of our choices, and God helps us bring them to their ultimate conclusion. For those who wish to spend eternity with God, He gave His own life to make it possible. For those who wish never to hear about Him again, He provides an eternity completely devoid of His presence. Either we agree to let His will be done in our lives, or He will agree to let our will be done. It’s our choice.
The passage in question actually begins in John 12:37 where the context is established;
“Even after Jesus had performed so many signs in their presence, they still would not believe in him.”
Since He knows the end from the beginning, God knew that when He sent His Son to Earth, He would be rejected. When the people persisted in their rejection, even in the face of incontrovertible evidence, He helped them take their desires to their ultimate conclusion by making it impossible for them to accept Him.
In John 12:42 we read , “Yet at the same time many, even among the leaders, believed in Him.”
By comparing verses 37 and 42 we can see that God was helping both believers and unbelievers get what they most wanted.