But notice the context here and other places when it speaks of God hardening the heart. The context indicates that such people had already turned away and afterwards God gave them over to their sinful rebellious heart. Romans chapter 1 describes this process:
Cause: "although they knew God, they neither glorified him as God nor gave thanks to him" Rom 1:21And so also in the case of Israel. They rebelled and then God gave them over. Thus God's answer would be that they first hardened their own heart as it is written, "do not harden your hearts as you did in the rebellion, during the time of testing in the desert" Heb 3:8 "Blessed is the man who always fears the LORD, but he who hardens his heart falls into trouble." Pr 28:14 Some may point out the argument concerning Pharoah where God says, "I will harden his heart so that he will not let the people go."Ex 4:21 But then again it is also written, "Why do you harden your hearts as the Egyptians and Pharaoh did? When he treated them harshly, did they not send the Israelites out so they could go on their way?" 1Sam 6:6, thus placing the responsibility upon Pharaoh and the Egyptians and us in general to control the state of our heart.
Effect: "God gave them over in the sinful desires of their hearts" Rom 1:24
Cause: "They exchanged the truth of God for a lie" Rom 1:25
Effect: "Because of this, God gave them over to shameful lusts." Rom 1:26
Cause: "since they did not think it worthwhile to retain the knowledge of God" Rom 1:28
Effect: "The gave them over to a depraved mind, to do what ought not to be done." Rom 1:28
Due to our sinful nature the natural state of our heart is one of sinful rebelliousness against God and we have the propensity to sin. By faith in cooperating with the grace of God we walk in righteousness contrary to our sinful nature because God gives us power to overcome. But if we rebel God may life his hand taking away that grace and allow the flood of sinful lusts to gain control of our flesh and again we are enslaved to sin and its consequences. Though this is not so much the case of those born of God since "No one who is born of God will continue to sin, because Godís seed remains in him; he cannot go on sinning, because he has been born of God." 1John 3:9 And thus you won't find those born of God living a lifestyle of sin. Yet even occasional sin can corrupt and subject us to discipline. Thus in any case "Watch over your heart with all diligence, For from it flow the springs of life."Pr 4:23