Question: If God knows the date I will die, is there any need to pray for healing? The same question can be asked about praying for others to be healed.
— Beth Helton, via email
Answer: Since God lives in the eternal now, he knows all things that have happened and that will happen. Although time unfolds for us, all time, past, present and future, is present to God at once. This does not mean, however, that we are fated or forced to do things God already knows, or that we have no freedom to act or capacity to influence outcomes. The simple fact of God knowing something ahead of time does not cause it to happen.
To use an imperfect analogy, suppose you were sitting up on a hillside and could see two trains coming around an opposite hillside on a single track; they are certain to collide. Your knowing this ahead of time does not cause the crash to happen. Rather the free-will actions or errors of engineers and track switchers are what cause the accident. It is like this with God, though far more comprehensively. It is not his knowledge of what will happen that, by itself, causes the event. Hence, we are not fated to do things, just because God has always known what those things would be.
Further, in God always knowing what we would freely choose to do, this includes the fact of whether we would pray for something or not. Hence, your request for healing for yourself or another in order to avoid or delay a likely death has always been known to God, and he has already accounted for your prayer in his providential plan for everyone, including his knowledge of the day we will die to this world. So, we who live in the unfolding of time, should certainly do as we are told: namely, to pray so as to positively affect outcomes. We play a role in God’s providence by doing what he has always known we would do, and our doing it fulfills and influences God’s providence from all eternity.