This man basically studied the bible from cover to cover to find all there is to say about prayer, and it is powerful to say the least. It forces you to think - to examine your prayer life according to God's Word, and in many ways it indirectly confronts you with how your prayer life reflects your faith in God. All this being said, it does what any good Christ-exalting book should - it teaches you, through scripture, to come closer to God and to seek him that he may be glorified.
This is a great book on prayer. It gives me a better understanding on how to pray and how to approach God in praying. It also encourages me to pray more.And to pray without ceasing. It's worth the money.