John 12:37-40 WEB
But though he had done so many signs before them, yet they didn’t believe in him,  that the word of Isaiah the prophet might be fulfilled, which he spoke, “Lord, who has believed our report? To whom has the arm of the Lord been revealed?”  For this cause they couldn’t believe, for Isaiah said again,  “He has blinded their eyes and he hardened their heart, lest they should see with their eyes, and perceive with their heart, and would turn, and I would heal them.”
How can we be responsible for God blinding our eyes and hardening our hearts? This is the very thing Paul addressed in chapter 7 of Romans. It brings new meaning to the idea of being saved by grace. We are saved by grace but are rewarded for our choices. Those who seek the Lord with humility will find him. The Word says that the one who has some will be given more and the one who has little will lose even what they have (Mat 25:15-28). This gives us insight into how to respond to this passage.
If we seek God, he will soften our hearts and open our eyes to be able to see him. Seeking God is easy. It is reading the Bible, praying, and attending public worship. We can also seek God with our behavior. On the other hand, we can also push God away with our behaviors. If we deliberately sin God will harden our hearts so that we continue to sin. Of course, if we deliberately walk in righteousness the Lord will soften our hearts so we walk in more righteousness.
The Lord is righteous. He does not cast anyone away from himself who walks in righteousness and holiness. The Word says those he foreknew he predestined to be sons of God (Rom 8:29). It is not that God is fickle. It is that God knows the future. God knows who will choose him and who will not. Of those that choose him, he creates opportunities for success. For those who are never going to choose him, he gives over to sin and unrighteousness. The primary thing we can do to ensure that God continues to open our eyes is to seek God and walk in righteousness.
Lord, please open my eyes so I can see you and understand your will. Soften my heart so I recognize sin in myself and give me the chance to repent. I long to be both saved and to have a vibrant relationship with you, Father. In Jesus’ name, amen.