"Monks, if those who have gone forth in other sects ask you, 'In what are all phenomena rooted? What is their coming into play? What is their origination? What is their meeting place? What is their presiding state? What is their governing principle? What is their surpassing state? What is their heartwood? Where do they gain a footing? What is their final end?': On being asked this by those who have gone forth in other sects, how would you answer?"
"For us, lord, the teachings have the Blessed One as their root, their guide, & their arbitrator. It would be good if the Blessed One himself would explicate the meaning of this statement. Having heard it from the Blessed One, the monks will remember it."
"In that case, monks, listen & pay close attention. I will speak."
"As you say, lord," the monks responded.
The Blessed One said, "Monks, if those who have gone forth in other sects ask you, 'In what are all phenomena rooted? What is their coming into play? What is their origination? What is their meeting place? What is their presiding state? What is their governing principle? What is their surpassing state? What is their heartwood? Where do they gain a footing? What is their final end?': On being asked this by those who have gone forth in other sects, this is how you should answer them:
"'All phenomena are rooted in desire.[1]
"'All phenomena come into play through attention.
"'All phenomena have contact as their origination.
"'All phenomena have feeling as their meeting place.
"'All phenomena have concentration as their presiding state.
"'All phenomena have mindfulness as their governing principle.
"'All phenomena have discernment as their surpassing state.
"'All phenomena have release as their heartwood.
"'All phenomena gain their footing in the deathless.
"'All phenomena have Unbinding as their final end.'
"On being asked this by those who have gone forth in other sects, this is how you should answer."
The Commentary goes on to say that the statement, "All phenomena are rooted in desire," deals exclusively with worldly phenomena, whereas the remaining statements about all phenomena cover both worldly and transcendent phenomena. There seems less reason to follow the Commentary's first assertion here, in that the noble eightfold path, when brought to maturity, counts as transcendent, and it is obviously rooted in a skillful form of desire.
As for the transcendent in its ultimate form, the phrase "all phenomena" as used in this sutta does not cover Unbinding, as Unbinding is not rooted in anything and, as the final statement indicates, it constitutes the final end of all phenomena. Thus this sutta would seem to belong to the group of suttas that would not classify Unbinding as a phenomenon. (On this question, see the note to AN 3.134.)
See also: MN 1.