This is what wanderers of other sects prescribe as solitude with respect to lodgings: a forest, the foot of a tree, a charnel ground, remote lodgings in forests and jungle groves, the open air, a heap of straw, a chaff-house. That is what wanderers of other sects prescribe as solitude with respect to lodgings. These are the three kinds of solitude that wanderers of other sects prescribe.
In this Dhamma and Discipline, bhikkhus, there are these three kinds of solitude for a bhikkhu. What three? Here, (1) a bhikkhu is virtuous; he has abandoned immorality and remains secluded from it. (2) He holds right view; he has abandoned wrong view and remains secluded from it. (3) He is one whose taints are destroyed: he has abandoned the taints and remains secluded from them