It is communion with God in the most direct, experiential way. Christians must pray. We cannot substitute anything in the place of prayer. Although everything good done by man glorifies God, the specific activity of prayer must be retained and perfected. If you are not successful in your prayer, do not expect success in anything.
Prayer is the root of all.
We are in God. Prayer is not merely the recitation of words. Prayer may begin by reading or saying the words of prayers. But a mere reading or saying of words, without feeling or attention, is not prayer. It is not even poor prayer.