Ben Patterson authored a great book on prayer, Deepening Your Conversation with God – Learning to Love to Pray.  The last chapter (pp157-171) describes the importance of corporate prayer in the life of a congregation.

Unity is one reason:

“…Jesus prays to the Father, ‘I in them and you in me.  May they be brought to complete unity to let the world know that you sent me and have loved them even as you have loved me’ (John 17:23). Note that Jesus claims for Christian unity a power he gives only to the Holy Spirit, to nothing and no one else – the power to persuade the world that he is indeed the One sent from God, ‘to let the world know that you sent me.’  The greatest argument for the authority and identify of Jesus does not have to come from philosophers and theologians and apologists.  It can come from the simplest believers who will live together in the unity of the Holy Spirit!

Why does unity have this kind of power?  One reason is that when we live together in love and harmony, it can mean but one thing: that each of us has ceased being his own lord and has submitted himself or herself to the Lord.

So what does this have to do with corporate prayer?

There can’t be one without the other – no genuine corporate prayer without unity, no real unity without corporate prayer.  If prayer is the deepest communion we can have with our Father God this side of heaven, how can we have this intimacy if we are at loggerheads with  other brothers and sisters in his family?  It can’t be done.  When we are less than one with each other, our oneness with Jesus is broken and incomplete.  So then are our prayers.  That’s why Paul says to Timothy, ‘I want men everywhere to lift up holy hands in prayer,’ and then adds, ‘without anger or disputing’ (1 Tim.2:8)”

 

There is power in presenting unity to the world, and corporate prayer goes with the unity.  Patterson presents an example of the power of prayer:

“After the first Great Awakening, three churches in Ipswich, Massachusetts covenanted to pray.  In each congregation, cell groups would meet weekly to agree in prayer.  Monthly, the separate congregations would then gather the cells and conduct all-church prayer meetings of agreement.  Then quarterly, all three would come together  for the same kind of paying.  This pattern was followed faithfully, without interruption, for a century. Two remarkable things happened during this time.  All three churches reported periodic harvest or “ingatherings” of souls, in which there would be a number of new believers brought into the congregations, about every eight to ten years.  Also, during this time, all of New England was being swept by Unitarianism.  But not these three churches.  They remained firmly true the faith while apostasy swirled around them, but not over them.  Around the time of the Civil War, the prayer meetings ceased.  Within five years these churches all capitulated to Unitarianism!”