Why Prayer? - Isaiah 37:21

Then Isaiah the son of Amoz sent to Hezekiah, saying, “Thus says the Lord, the God of Israel: Because you have prayed to me concerning Sennacherib king of Assyria - Isaiah 37:21

There is a school of thought among the many Christian denominations that God has already decided what His decrees will be and thus prayer does not and cannot change His will; therefore; why pray? A more sobering look at why we are to pray awaits anyone with a Bible in their possession to understand that God does indeed answer prayer. Jesus Himself said, “Ask, and it will be given to you; seek, and you will find; knock, and it will be opened to you.” - Matthew 7:7. Do these sound like useless and ineffective commands? Does this sound like God doesn’t answer prayer? Doe this sound like God has already made up His mind?
There are only a few reasons why God doesn’t answer prayer. One would be what the Apostle James regards as an improper request, not because our prayer is improper but because we have asked for something that is not within the will of God. “You ask and do not receive, because you ask wrongly, to spend it on your passions.” James 4:3. We must approach God in a manner appropriate to Him as our Creator, Sustainer, and Lord.
The Apostle John reiterates this approach when he writes - “And this is the confidence that we have toward him, that if we ask anything according to his will he hears us.”- 1 John 5:14. We must be certain that what we ask for fits within God’s certain will, even when His will does not placate our human desires. Our own mothers and fathers didn’t always give us what we wanted; God is no different in this small respect.
Another reason God will reject our prayers as insignificant is when we come to Him with sinful hearts. Naturally, we all come to God in such a manner because we are all sinners at heart. But approaching God with humble hearts in reverence and contrition will often loosen us from the worldly bonds that so often darken our souls with unrepentant sin. “If I had cherished iniquity in my heart, the Lord would not have listened. But truly God has listened; he has attended to the voice of my prayer.” - Psalm 66:18-19. Bringing our prayer requests to God while we bask in our sinfulness will always ring with the hollow and forlorn sound of ‘the weeping and gnashing of teeth.’
As regenerated children of God, we have been instructed to - “Rejoice always, pray without ceasing, give thanks in all circumstances; for this is the will of God in Christ Jesus for you.” - 1 Thessalonians 5:16-18. Again, we see that this is the will of God for us. The effectiveness of our prays made according to God’s will is hardly up for debate. Among the many clear accounts of answered prayer are this one - “Elijah was a man with a nature like ours, and he prayed fervently that it might not rain, and for three years and six months it did not rain on the earth. Then he prayed again, and heaven gave rain, and the earth bore its fruit.” - James 5:17-18.
We may never know what God’s plans involve or are to bring about. We know what His declared will holds for us but His decretive will is another thing altogether. Why does God cure one but not another? Why does He save one from harsh persecution and not another? Why does He allow the genocide against one nation and not another? Why does God allow one child to live yet another to die? The answer to these questions we can only speculate about. Our understanding of why God does things the way He chooses to appears to us (if at all) as though through a fog. But one day - “For now we see in a mirror dimly, but then face to face. Now I know in part; then I shall know fully, even as I have been fully known.” - 1 Corinthians 13:12.
Our prayers are commanded by God and if for that reason alone, let us pray.