"He has delivered us from such a deadly peril, and He will deliver us again. On Him we have set our hope that He will continue to deliver us, as you help us by your prayers. Then many will give thanks on our behalf for the gracious favor granted us in answer to the prayers of many."
~2 Corinthians 1:10-11
Now these verses just amazingly address the power of prayer. God had delivered Paul from some crazy horrible things. Part of that deliverance came because people helped with prayers for him. How wonderful is that? If you ever need a passage to remind yourself that your prayers matter, memorize this one.
We must pray as God leads because when we do things happen. I do not know why God works alongside us in this way. He does not need us. He is all powerful. I think it is just part of His love for us and His desire for intimacy with us.
So believer, know prayer is a gift, privilege, and responsibility. Do it as God leads. It matters. We should be thankful for that.