From the Holy Buddhist Tipitaka: Bhaya-bherava Sutta: Fear & Terror

When priests or contemplatives in their bodily activities resort to isolated forest or wilderness dwellings, it’s the fault of their unpurified bodily activities that they give rise to unskillful fear and terror. But it’s not the case that I am unpurified in my bodily activities when I resort to isolated forest or wilderness dwellings. I’m purified in my bodily activities. I’m one of those noble ones who are purified in their bodily activities when they resort to isolated forest or wilderness dwellings. Seeing in myself this purity of bodily activities, I felt even more undaunted about stay in the wilderness.