Unoccupied churches are a little creepy to me, day or night. In daytime, they are lit by light filtered through stained-glass. At night, they are dark as pitch. At any time, they are quite, still caliginous places.

1 hour ago, drpaladin said:

The older the church, the darker it tends to be with dark woods and light dimming stained glass, plus you're surrounded by grotesque and macabre imagery like someone being tortured to death on a cross or pierced by multiple arrows.

Modern churches are so sterile and vanillaly marshmallow.

And don't forget that many of the older churches have a cemetery on the grounds or very nearby, so that adds to the caliginous effect as well.