I came across this wonderful quote from Abbot John Chapman, who wrote:
The time of prayer is passed in the act of wanting God. It is an idiotic state, and feels like the most complete waste of time, until it gradually becomes more vivid. The strangest phenomenon is when we begin to wonder whether we mean anything at all, and if we are addressing anyone, or merely repeating mechanically a formula we do not mean. The word God seems to mean nothing. If we feel this curious and paradoxical condition, we are starting on the right road, and we must beware of trying to think what God is and what He has done for us, etc.; or what we are before Him, etc., because this takes us out of prayer and spoils God’s work, as St. John of the Cross says.