For God is silence, and in silence is he sung by means of that psalmody which is worthy of Him. I am not speaking of the silence of the tongue, for if someone merely keeps his tongue silent, without knowing how to sing in mind and spirit, then he is simply unoccupied and becomes filled with evil thoughts: … There is a silence of the tongue, there is a silence of the whole body, there is a silence of the soul, there is the silence of the mind, and there is the silence of the spirit.

(Desert Fathers)