Why pray, when God is all-powerful? God can do whatever God pleases. God created the universe, set it in motion. Why pray? How could we ever hope to move the great God's hand?
We pray because something in us longs to reach out to God. What child is able to accept that her parents will do whatever is right for her, so she need never ask for anything? A child asks. The answer may be "no", or "wait"; but that doesn't stop her asking. To call God "Abba" is to want, to need to pray, to communicate with the loving God.
Pray because that is how God's will is done. It's a great mystery. We can't say that God wouldn't act out of love for us if we didn't pray, but Jesus believed that prayer made things happen, got things done.
Prayer isn't so much telling God what to do as it is discerning God's will, asking God to act, and trusting God to do what is best.
Why pray? Pray because God wants to hear us, and waits to answer us. "Ask. Seek. Knock," Jesus said. Knock and the door will be opened. Through the open door you will find your answer, the loving God. Pray because prayers are answered.
Pray the Lord's Prayer from Luke 11 slowly, savouring each phrase.
Luke 11:2-4 – Jesus said to them, "When you pray, say: 'Father, hallowed be your name, your kingdom come. May your will be done on earth as it is in heaven. Give us each day our daily bread. Forgive us our sins, for we also forgive everyone who sins against us. And lead us not into temptation but deliver us from the evil one.'" Amen.