"There I sank to my knees. I had reached my destination. I was ready to meet the source of the summons that had disturbed my rest. I was in a posture of prayer, but I had nothing to say.  I knelt there quietly, allowing the sense of the presence of a holy God to fill me. The beat of my heart was telltale, a thump-thump against my chest. An icy chill started at the base of my spine and crept up my neck. Fear swept over me.  I fought the impulse to run from the foreboding presence that gripped me.
The terror passed, but soon it was followed by another wave. This wave was
different. It flooded my soul with unspeakable peace, a peace that brought instant rest and repose to my troubled spirit. At once I was comfortable. I wanted to linger there. To say nothing. To do nothing. Simply to bask in the presence of God.
That moment was life transforming."

From "The Holiness of God" by R.C. Sproul Chapter 1