I am afraid of the dark. Seriously. And for years I worked in the dark, and not just figuratively (although there was that), literally in the dark. I worked in a building that the designers never considered the possibility that people might enter through the back of the building. None of the light switches were at the rear doors, only the front doors. I literally had to walk across a dark, unlit, room filled with darkness (badness), to turn on the light. It is an exercise in discipline for me to be in a dark place, literally and figuratively.
A church I served offered communion to people one morning a week as they were on their way to school or work. One hour, early in the morning. Our practice was to leave the light off, and allow the sanctuary to be illuminated only by a few candles and the spots on the stained glass windows. Only problem for me was the fact the lights were on a timer, and as the days grew shorter the lights extinguished before the sunlight appeared. And it was in those receding dark and emerging light moments that the place became the thinnest of places.