This is my experience, strictly my opinion and my answer: I know that the silence and the act of making the rock stacks is very meditative ~ It is my belief that any time you go into the silence is where/when we can tap into Source.
Any time you offer a loving gesture, thought or action ~ it can be celebrated as communion with the Absolute.
Everything is of this endless, loving energy Field of Potential, this Higher Power ~ so everything we do is in communication and communion with God.
What we see as prayer or the act of praying, I believe is just our earthly definition to describe our end of the communication. Our faith strengthens and clears the connection to this Loving, powerful, ever present Force that is within all of us.
Basically, I believe everything we do, say, feel and think can be defined as “prayer” ~♥