Why Pray if God Already Knows Everything?

Jesus said it plainly in the Sermon on the Mount:

If you stopped reading there, you might think prayer was pointless. But look at the verses on either side. Just before, Jesus warns against “vain repetitions, as the heathen do: for they think that they shall be heard for their much speaking” (Matthew 6:7, KJV). Just after, He says, “After this manner therefore pray ye: Our Father which art in heaven” (Matthew 6:9, KJV), and gives the Lord's Prayer.

So God's knowledge is not a reason to stop praying. It is a reason to stop performing. You do not have to pile up words, find the right formula or explain yourself to get God's attention. He already knows, and He already cares. That frees you to pray simply, honestly and often, like a child talking to a father. David knew this: “For there is not a word in my tongue, but, lo, O LORD, thou knowest it altogether” (Psalm 139:4, KJV). And he kept praying.

Parents usually know what kind of day their children have had before they hear a word about it. They still want to hear it. The point of the conversation was never the information; it was each other.

Prayer is like that. God does not need our reports, but He wants us. “Draw nigh to God, and he will draw nigh to you” (James 4:8, KJV). The Psalms invite us to “pour out your heart before him” (Psalm 62:8, KJV), not to brief Him. Jesus called His disciples friends, not servants (John 15:15), and friends talk.

Jesus Himself, who knew the Father perfectly, made time to pray: “And in the morning, rising up a great while before day, he went out, and departed into a solitary place, and there prayed” (Mark 1:35, KJV). He was not informing His Father of anything. His prayers were the life of a relationship, not a list of requests.

The Bible says yes. God has chosen to do some things in answer to prayer. James says it bluntly: “ye have not, because ye ask not” (James 4:2, KJV). And:

James then points to Elijah, “a man subject to like passions as we are” (James 5:17, KJV), who prayed and the rain stopped, then prayed again and it rained. The Old Testament is full of such moments. When King Hezekiah was dying and prayed with tears, God sent him word: “I have heard thy prayer, I have seen thy tears: behold, I will heal thee” (2 Kings 20:5, KJV).

None of this means prayer is a lever that makes God do what we want. It means God has given His people a real part in His work, the way a good father lets his children help with something he could easily do alone. Our prayers are one of the means He has chosen to use.

This question assumes that God's plan and our prayers are rivals. The Bible treats them as partners: God's plan includes our prayers. Thomas Aquinas put it this way: we pray “not that we may change the Divine disposition”, but to receive what God has planned to give in answer to our prayers (Summa Theologiae II-II, question 83, article 2, in the English Dominican translation).

Jesus showed what praying inside God's plan looks like. In Gethsemane He knew why He had come, and still He asked honestly for another way, ending, “nevertheless not my will, but thine, be done” (Luke 22:42, KJV). Prayer is not a way around God's will. It is how we bring our real desires to Him and learn to want what He wants. When we pray, “Thy will be done in earth, as it is in heaven” (Matthew 6:10, KJV), we are asking to be part of His plan, not trying to cancel it.

Christians have answered this in more than one way, and the Bible gives material for each view.

God does not change, and prayer is part of how He works. Many Christians, following theologians such as Thomas Aquinas and confessions such as the Westminster Confession, which calls God “immutable”, hold that God's purposes never change: “For I am the LORD, I change not” (Malachi 3:6, KJV). On this view, God willed from eternity to act in answer to prayer, so prayer is a real cause of real results, but it does not alter His eternal plan. Passages that say God “repented” (Exodus 32:14, KJV) are read as describing His response in human terms: the same unchanging God meets a repentant people with mercy instead of judgment.

God responds, and the future is partly open. A smaller group of Christians, often called open theists, hold that God knows every possibility but that the future is not yet settled, so prayer can change what God decides to do. They read Moses pleading for Israel (Exodus 32:11-14) and the healing of Hezekiah (2 Kings 20:1-6) at face value. This view is a minority one, and it has been sharply debated among evangelicals.

Holding both together. Many other Christians, including Arminian believers who stress human freedom, affirm both that God knows the future fully and that He truly listens and responds, without claiming to explain exactly how the two fit together.

What every view shares matters more than where they differ. God hears. Prayer is not wasted. And God is not a machine that hands out answers. He says no to selfish prayers: “Ye ask, and receive not, because ye ask amiss” (James 4:3, KJV). Sometimes He says no to good prayers too, as Paul found when he asked three times to be freed from his thorn in the flesh and heard instead, “My grace is sufficient for thee” (2 Corinthians 12:9, KJV).

In the King James wording, “Be careful for nothing” means: do not be full of care, or worry, about anything. Notice the promise. Paul does not say every request will be granted. He says that the person who brings everything to God will be kept by a peace that goes beyond understanding. Prayer changes the one who prays.

Aquinas made the same point: we pray not to tell God our needs but to remind ourselves that we depend on His help. Over time, prayer reshapes what we want. Praying for enemies softens us toward them (Matthew 5:44). Thanking God trains us to notice His gifts. Confessing sin keeps us honest. Bringing the same fear to God again and again slowly turns it into trust. And when we do not know what to pray, “the Spirit itself maketh intercession for us with groanings which cannot be uttered” (Romans 8:26, KJV).