4.
The Discourse on Existence
164.
"There are these three existences, monks.
Which three?
Sensual-sphere existence, fine-material-sphere existence, immaterial-sphere existence -
these, monks, are the three existences.
For the direct knowledge, full understanding, utter elimination, and abandoning of these three existences, monks, etc.
this noble eightfold path is to be developed."
The fourth.