Therefore, when a person refuses to come to Christ it is never just because of lack of evidence or because of intellectual difficulties: at root, he … - William Lane Craig

Heaven may not be a possible world when you take it in isolation by itself. It may be that the only way in which God could actualize a heaven of free creatures all worshiping Him and not falling into sin would be by having, so to speak, this run-up to it, this advance life during which there is a veil of decision-making in which some people choose for God and some people against God. Otherwise you don't know that heaven is an actualizable world. You have no way of knowing that possibility.

In general, Western culture is deeply post-Christian. It is the product of the Enlightenment, which introduced into European culture the leaven of secularism that has by now permeated Western society. While most of the original Enlightenment thinkers were themselves theists, the majority of Western intellectuals today no longer considers theological knowledge to be possible. The person who follows the pursuit of reason unflinchingly toward its end will be atheistic or, at best, agnostic.

What good does it do to pray about anything if the outcome is not affected? I would say when God chooses which world to actualize, he takes into account the prayers that would be offered in that world. We shouldn't think prayer is about changing the mind of God. He's omniscient; he already knows the future, but prayer makes a difference in that it can affect what world God has chosen to create.