Much of the devotional literature on prayer is focused on those things which help us to pray – posture, exercises, liturgies, habits. But, while they may be helpful, none of them is necessary. The focus of the Bible is instead on Christ and his sufficiency. There is nothing we can do to make our prayers more effective before God. Any such notions are a return to paganism – it is to suppose that we can manipulate or placate God. As Ronald Dunn puts it, the floor of the throne room is sprinkled, ‘not with the sweat of my good works, but with the of his sacrifice’. The ‘posture’ that the Bible commends is a humble and contrite heart
From the book "The Message of Prayer: Approaching The Throne Of Grace (The Bible Speaks Today Themes)"