The Two State Dimensions of
Nibbãna:

There is Nibbāna here
and now in this very life:
We call it
Sa-upadi-sesa-Nibbāna i.e. Nibbāna with traces of the
substrates of becoming
- some subtle forms of clinging - still remaining in the
mind...
Then there is the final Nibbāna, with no substrates for being, or fuels for
any form of
becoming left remaining: This is called An-upadi-sesa-Nibbāna.
The Blessed
Buddha explained it thus: The 2 aspects of Nibbāna:
Bhikkhus, there are these two Nibbāna-elements. What are the two?
The
Nibbāna-element with residue left, and
the Nibbāna-element without any traces of
substrate left. What, Bhikkhus, is the Nibbāna-element with residue left?
Here a
Bhikkhu is an Arahant,
one whose mental fermentations is silenced, who has fulfilled
the Noble life, who has done all what had to be done, who has laid down the burden, attained
the goal,
who has destroyed the bondages of being,
and who is completely released through
final knowledge. However, his five sense
abilities remain unimpaired. Through these he still
experiences what is agreeable and
what is disagreeable,
and he feels both pleasure and pain.
It is the extinction of greed, hate, and ignorance in his
mind that is called this
Nibbāna-element
with residue left. Now what, Bhikkhus, is the Nibbāna-element with no residue remaining?
Here a
Bhikkhu is an Arahant,
one whose mental fermentations is silenced, who have fulfilled
the Noble life,
who has done all what was to be done, who has laid down the burden, attained
the goal,
who has destroyed the bondages of being, who is fully released through final knowledge.
For him, here in this very life, all that is experienced,
not being delighted in, will grow cold right
there and then. and cease.
That is called Nibbāna-element with no residue left.
These, Bhikkhus, are the two Dimensions of Nibbāna...

These two Nibbāna-elements were thus made
known by the All-Seeing One, confident
and detached:
The first is the element with substrates of being remaining,
realized here
and now, but with rebirth re-becoming destroyed. The other, having no residue left for
the future,
is that wherein all modes of being utterly cease.
Having understood this
unconstructed and unconditioned state, released in mind, with the
navel string to becoming
eliminated,
they attain to the sublime essence of all states.
Delighting in calming and ceasing
of all craving, those steady ones have left all
being, and any becoming irreversibly behind...
Comments:
Sa-upadi-sesa-Nibbāna i.e.
Nibbāna with traces of becoming
remaining is the state of the still
living Arahant, who still has a body, feelings, perceptions, mental constructions and consciousness
as a remaining result and delayed effect of clinging in his past, the
kammic effects of which have
not yet been fully exhausted...
Final Nibbāna with no substrate
fuels for being or becoming left remaining: An-upadi-sesa-Nibbāna
is the state of the Arahant after death, where body, feeling, perception, mental construction and
consciousness have irreversibly ceased without ever
re-arising anywhere anymore.. This is the only
end of the Samsaric Suffering inherent in the ever recurring
rebirth, ageing, sickness and death...
Source; Thus Was it Said: Itivuttaka II.17; Iti 38

More on this uncreated
state - Nibbāna (Sanskrit = Nirvana):
Climax of Calm,
Final Freedom,
The
Proximate Cause, Peace,
What_is_Nibbana,
Nibbana or non-return,
Reaching Peace,
The_Uncreated,
The_Signless_Nibbana,
Nibbana_True_Peace,
The_Entrance,
The_Unborn_State,
How_to_Enter,
Nibbana_Still,
Imperturbable_Equanimity,
Nibbāna...