 How long should you pray daily in order to be used by God with great power? This kind of question assumes that God's power depends upon our devotion. Let me explain. To be clear, you should pray every day and all throughout the day. Additionally, you should set aside time that's totally devoted to just the Lord. You need both spontaneous prayer and scheduled secluded prayer. And of course, every believer should live clean and in the awareness of the Holy Spirit's presence. But I don't count the hours I pray, just like I don't set a timer when spending time with my Jessica. If we count hours in prayer like points, then when God does use us, we might be deceived into thinking that his power moved because of our prayers. Live a yielded life and let God do with it what he will. Don't have faith in your own prayer life. Don't even have faith in faith. Have faith in Jesus. Give him all the glory for however he chooses to move in and through you.