The inevitable Dissolution of
All
Phenomena:

All past constructions have vanished.
All present construction is vanishing.
All future constructions will vanish.
All phenomena are sure to cease.
All being in existence will be cut off.
All becoming is therefore truly a Terror!
It is
void, vain and empty like an empty village, like a
tumour, a cancer. Like a trap, a burning pit!
About this
both sweeping and stunning Generalization the
Ancients Elders said:
The substitution of the Object.
The transference of the Understanding.
The power of redirecting thought - these
are the Insights following real Reflection.
Defining both to be
alike. By inference from that same object,
Intent on ending all
- these are insights into the characteristics
of decay and fall.
Having reflected on an object,
one contemplates dissolution
of that thought,
Appearance then as Empty - this
is insight into higher Understanding.
Clever in the three contemplations:
The arising,
fall, and dissolution of all phenomena.
And in the fourfold Truth too. Skilled in the three
characteristic appearances:
Transience, suffering,
and no-self the various diverse views cannot shake him.
With view of what is
present
purified. He infers the past and future to be alike:
He know that all constructions
will disappear like a dew drop in the morning sun.
The
clusters of clinging
cease and nothing else ever were. The breakup of these groups is
known as Death. He observes their continual decay unwaveringly
as one who drill a hole
in a jewel
with a diamond..
Visuddhimagga-Magga (The Path of
Purification) XXI

As the expert drilling a jewel with a diamond tool only pays attention to the hole and not
to the colour of the jewel, so do the meditator too, wisely keep his mind fixed
and focused
on the
Ceaseless
Dissolution of all conditioned construction, and not on the constructions
(mental
formations) themselves..
Visuddhimagga-Magga commentary
(Paramatthamanjusa)
[830]
And he who regards the World
as one who watches a bubble, as one views a mirror
image,
is unseen by Mara, Death - the King.
Dhammapada
170.
When one sees the dissolution of reflection on causes
and conditions, this thinking in itself
being an construction - a mental formation -
the ancients elders (poranas) said:
He sees with insight both the known and the knowledge.
Knowledge is what is known and
understanding is the act of understanding that.
Seeing with insight is always seeing it as it
verily
really just is: Impermanent, miserable and impersonal..