Even the highest states of mundane samadhi like the 8th jhana of
neither perception nor non-perception is still a state of
samsara.
Samsara is any temporary states that are still not freed from
the afflictions of ignorance, the mind's affliction, desires,
clinging and attachment, and so on.
The jhanas are very profound meditative states, but beings who
mastered such states without attaining enlightenment will only at
best gain rebirth as one of these meditation gods. They will still
die eventually after millions or billions of years, and take birth
again in another realm, possibly in the 3 lower realms if they have
past bad karma. Therefore heaven is not safe and secure according
to Buddhism. Nothing is secure because you eventually die and get
reborn. They are still a realm of samsara, and samsara means the
world of suffering. The world of cyclic existence and rebirth,
which means one keeps cycling from one birth to another, from one
plane/realm of existence to another, continuously and
uninterruptedly, according to one's karma. And Buddhism aims to end
all sufferings even in this very lifetime (and thus in the future
lifetimes, since one cuts off the causes for uncontrolled
rebirth).
The 8 jhanas are made of 4 form jhanas and 4 formless jhanas.
The first four jhanas have corresponding heavens where the Brahmas
live in a world of forms. This is contrasted to the lower heavens,
which is below the 8 jhanas heaven. The lower 6 heavens belong to
the plane of sensual desires. In these 6 heavens, devas still have
sex and enjoy other pleasures and enjoyment of their senses.
In the 4 form brahma realm, those beings do not have sex, and do
not enjoy pleasures of senses. Rather their bliss is of a subtle
kind that is not born of sensual pleasures.
For example the Buddha described the first level Jhana as
follows:
“he enters & remains in the first jhana: rapture &
pleasure born from withdrawal, accompanied by directed thought
& evaluation. He permeates & pervades, suffuses & fills
this very body with the rapture & pleasure born from
withdrawal. Just as if a skilled bathman or bathman's apprentice
would pour bath powder into a brass basin and knead it together,
sprinkling it again & again with water, so that his ball of
bath powder — saturated, moisture-laden, permeated within &
without — would nevertheless not drip; even so, the monk
permeates... this very body with the rapture & pleasure born of
withdrawal. There is nothing of his entire body unpervaded by
rapture & pleasure born from
withdrawal.”
Note: pleasure born from withdrawal. It is not a pleasure born
from sensual experiences. But from detachment and absorption into a
state of bliss that suffuses the whole body but is not born from
sensual experiences, not from outer stimulus. This is actually a
state that can be experienced in meditation and I also have some
prior experience of this. This type of bliss is actually much more
profound, subtle, beautiful and more powerful bliss than any kind
of sensual bliss, including orgasm, drugs, etc. It does not derive
from outside stimulus.
Now, the 8 jhanas get subtler and subtler as you enter into
higher states of jhanas, from the 1st, to the 2nd, to 3rd and so
on.
The first four jhanas are form jhanas, where beings in these 4
jhana planes still have attachment to corporeal form and body, even
though they do not experience sensual desires. However in the 4
formless jhanas, it is totally formless, i.e. infinite space,
infinite consciousness, nothingness, and neither perception nor
non-perception. Such beings do not have a body or form, they do not
have attachment to any forms, their only state of existence is this
formless space, consciousness, nothingness, or neither perception
nor non-perception. It is a much subtler state of bliss and they
can stay there for millions or billions of years until their karma
and absorption runs its own course and they will again cycle
through the various samsara realms.
Now, attaining enlightenment is a different matter from
attaining these subtler states of meditative absorption.
Enlightenment concerns about insights into the nature of reality
where one penetrates and realises the impermanent, empty,
dissatisfactory, no-self, dependently originated nature of all
experience. It is through these insights that one progressively
breaks subtler and subtler clingings and attachment (known as the
ten fetters) until eventually one becomes entirely free from the
cycle of rebirth in samsara.
It should be noted that there are two types of meditation:
samatha meditation is one-pointedness, concentration meditation
that leads to jhana experience but not liberation or enlightenment.
There is also vipassana meditation which means investigating and
being aware of the true nature of all sensations and experiences in
our direct present sensate reality. This will lead to enlightenment
and liberation. Some people practice samatha meditation first to
build a strong concentration foundation for futher vipassana
practice, while some people go straight into vipassana (insight
meditation) from the beginning.
In the Hinayana path, there are 4 stages of enlightenment,
called the stream enterer, the once returner, the non returner, and
the Arhant.
The stream enterer had a sudden glimpse of Nirvana and had some
experiential, but not full, realisation of no-self. He will as a
result give up the 3 lower fetters of false views of
personality-self, the clinging to useless rituals and
superstitions, and any skeptical doubts about the triple gems
(because he already has a direct experience of what is being
spoken). A stream enterer is guaranteed to attain full liberation
(Arhantship) in no more than 7 lifetimes even if he dies before he
could complete his journey. He is also assured that he will no
longer fall into the 3 lower realms of hell, ghosts and animals,
and could only be reborn either in the human or the deva (heaven)
realm. However if he practices hard, he can ascend all the way to
complete liberation in his very life before dying, so it is not
necessary to wait for his next life.
The non-returner, second stage, has a higher level of experience
and realisation and as a result removed sensual craving and ill
will, the next 2 fetters, to a high degree. However he has not
completely removed those 2 fetters. As a result, he is guaranteed
to attain full liberation either in the human realm or the deva
realm in the next life, even if he dies before he could complete
his journey. However if he practices hard, he can ascend all
the way to complete liberation in his very life before dying.
The non-returner, third stage, has has a higher level of
experience and realisation and as a result has completely removed
sensual craving and ill will, the next 2 fetters. And because he
has cut off all sensual clinging, and removed such a fetter, it
implies that he has cut off the root cause of rebirth in the
Sensual realm of existence, which is the realms before the jhana
realm. However at this stage, the anagami has not cut off the 5
higher fetters, which include clinging to form and formless states
of jhana. He has not cut off craving and clinging to corporeal
form, and also attachment to jhanic states. That is why as a
result, if he dies before he attains full Arhatship, he will be
reborn in the 4th Jhana plane and attain Arhatship from there, even
though he will no longer return to the sensual realm or the human
realm.
The Arhant, has basically cut off all of the 10 fetters and as a
result has completely freed himself from being bound to the 3
states of existence, the sensual plane, the form jhana plane, and
the formless jhana plane of samsaric rebirth.
The ten fetters are in total:
