We can't expect our prayer-life to exist as a separate entity from the rest of our lives. The way we live during every other part of our day does affect the way we pray. It affects the effectiveness and power of our prayers. When we abide in Christ, our prayers avail much. When we walk in the Spirit, our prayers fulfill God's will. The Holy Spirit is there, waiting and ready to carry us into Christ's ongoing intercessory work; but if we refuse to be holy as He is holy, and are always living contrary to that new nature, how can we expect to be able to enter into fellowship with God, to pray in Christ's name, and to experience an outpouring of the Holy Spirit into a world that so desperately needs to be reached? We must ask ourselves the honest question: "Who am I, really? What is my life, really? Am I really growing stronger spiritually day by day and week by week? Do I really have the kind of integrity and character God expects me to have? Am I a willing and worthy (or useable) vessel?" These are serious questions for serious followers of Christ. He has promised to make us useful. We just need to let Him.
"And so once again the lesson comes: What our prayer avails, depends upon what we are and what our life is. It is LIVING (emphasis mine) in the Name of Christ that is the secret of praying in the Name of Christ; LIVING (emphasis mine) in the Spirit that fits for praying in the Spirit." - Andrew Murray