Calvin: Six Purposes of Prayer

Joel Beeke & Brian Najapfour in Taking Hold of God: Reformed & Puritan Perspectives on Prayer list what John Calvin (Institutes: book 3, chapter 20) sees as the six (at least) purposes of prayer.

1. To fly to God with every need and gain from Him what is lacking in ourselves to live the Christian life
2. To learn to desire wholeheartedly only what is right as we place all our petitions before God
3. To prepare us to receive God's benefits and responses to to our petitions with humble gratitude
4. To meditate on God's kindness to us as we receive what we have asked for
5. To instill the proper spirit of delight for God's answers in prayer
6. To confirm God's faithful providence so that we may glorify Him and trust in His present help more readily as we witness His regularly answering our prayers

"All of these purposes are designed to foster communion with God so that 'the promises of God should have their way with us.'" (quoting Niesel, Theology of Calvin, 157)

From Taking Hold of God, pg 31-32.

Prayer For Revival Should Never Be Parochial

...Asahel Nettleton in America knew the importance of communities praying for each other. At Milton he urged the Christians to pray for revival but then added ' Whether you do or not, it is possible there may be one, for Christians in other places have agreed to pray for you'! This is a reminder than in our praying for revival we should never be parochial and long for the touch of God only for ourselves; we must pray for those churches that do not pray for themselves, as well as for those that do.

Brian Edwards, Revival: A People Saturated With God, p84

Check out the other books on revival I'm using for my current sermon series.