So the Masters told me when I was in the first flush of enthusiasm for meditation. But actually you could say especially the greatest saints prayed.
Something I have noticed more and more, though it's been around a long time, is that if you ask someone if they believe in God they will often, assuming they say yes, redefine God to mean something else. So they might say that yes, I believe in God. He is the One Life or he is the Self that exists within us all or he is the unmanifested Void that exists in the space between vibrations or he is what I am in my truest and best self. But all this means he is not he at all. He is it.
I would question anyone who says he believes in God but then turns God into an impersonal force or abstraction or cosmic absolute. God is not an energy that we can tap into to further ourselves, even further ourselves spiritually. He is not an impersonal Nothingness even if that nothingness be regarded as the seedbed of all existence. That concept, by the way, applies more to the chaos of matter before it is 'breathed' on by God and stirred into active existence, and those who plunge in their meditations into the Void might consider whether they are actually engaging in a positive spiritual practice or returning their consciousness to its pre-created state which is not necessarily the way forward.
Mystical spirituality attracts two types of people. Those who love God and those who want to become God or believe they already are God. At the extremes these are represented by Christ and Satan which should sound a note of warning to the latter type who might see God as impersonal being and therefore regard the spiritual path as one of knowledge or awareness. So it is but it is primarily a path of love and if love is not the driving force for your spiritual journey you risk going off the road. Prayer is love. That is what it essentially is, and love is directed towards a personal being. God is a personal being not an impersonal energy and that is why the saints all pray. Certainly there are deep states of consciousness available to those who seek a God of impersonal being but these are outside Heaven. The perfection of prayer is what heaven is.