Udāna 1: Bodhivaggo
The Chapter (including the Discourses) about the Awakening (Tree)
2: The Second Discourse about the Awakening (Tree)
Thus I heard:
at one time the Fortunate One was dwelling near Uruvelā, on the bank of the river Nerañjarā, at the root of the Awakening tree, in the first (period) after attaining Awakening.
Then at that time the Fortunate One was sitting in one cross-legged posture for seven days experiencing the happiness of freedom. Then with the passing of those seven days the Fortunate One, after arising from that concentration, for the middle watch of the night, applied his mind thoroughly to conditional origination in reverse order:
“This not being so, that is not; from the ceasing of this, that ceases,
that is to say: from the cessation of ignorance, there is the cessation of (volitional) processes,
from the cessation of (volitional) processes, the cessation of consciousness,
from the cessation of consciousness, the cessation of mind and bodily form,
from the cessation of mind and bodily form, the cessation of the six sense spheres,
from the cessation of the six sense spheres, the cessation of contact,
from the cessation of contact, the cessation of feeling,
from the cessation of feeling, the cessation of craving,
from the cessation of craving, the cessation of attachment,
from the cessation of attachment, the cessation of continuation,
from the cessation of continuation, the cessation of birth,
from the cessation of birth, old age, death, grief, lamentation, pain, sorrow, and despair (all) cease,
and so there is a cessation of this whole mass of suffering.”
Then the Fortunate One, having understood the significance of it, on that occasion uttered this exalted utterance:
“When (the nature of) things becomes really manifest
To the ardent meditating brāhmaṇa,
Then all his doubts disappear,
Since the destruction of causes has been understood.”