OP: Whatever is,the question is quite clear: if you can reach a
state of emptiness , how can you state that Void is not part of a
higher consciousness (aka God) but it is just Void? If you “feel” the
Void during meditation and you call it nirodha samapatti for example,
how do you know that it is just Void instead of being Void before or
inside another greater Consciousness , which is perceived as Void
(Sunyata, as the Vedantists think and argue with you) but is higher
than that simple state of nothing ? (super consciousness pervading
everything)
I think we should put the record straight here and avoid distorting the original teachings of the Buddha, as found in the Sutta Pitaka. There is no "higher consciousness (aka God)" or "super consciousness pervading everything" or Atman or Brahman in the original teachings of the Buddha.
I understand your premise - if in meditation, you attained a state of void, then there must be some higher consciousness (aka God) that is perceiving it. This higher consciousness is usually attributed to God as the Self or Super Soul (Atman) in Vedanta. This is described in the Hindu text Bhagavad Gita 13.14.
Advaitin gurus would suggest you to ask "Who am I?" and discover that the true "I" is Atman, which is Brahman (God). The Atman is also the Eternal Witness, or the Cosmic Consciousness, the "I" of every self-conscious being. After attaining Self-Realization (where the little ego-self drops away), one would remain existing forever as this one single Eternal Witness or Cosmic Consciousness, that witnesses through every self-conscious being and even witnesses directly without any beings.
What did the Buddha teach?
The self (atta or Atma) is the idea or thought that arises out of the inter-operation or inter-working of the five aggregates (form, feeling, perception, mental formations and consciousness). This is similar to how music is created when different parts of a musical instrument works together. See Lute Sutta. How the five aggregates work together is described by Dependent Origination.
Sabbe dhamma anatta (Dhammapada 279) means that all phenomena (including Nibbana), is not self. If you break a musical instrument into pieces, you won't be able to find music in any of the constituent parts - Lute Sutta. If you look at the five aggregates, you cannot find the self there. The Buddha means here that there is no eternal and permanent core of one's being, that is the self, not even Nibbana.
Rather, the self is an impermanent changing idea, that arises and passes away from moment to moment, depending on the operation of the five aggregates, just as other mentally generated ideas.
And what about consciousness? The Buddha taught the following, from MN 38:
“Bhikkhus, consciousness is reckoned by the particular condition
dependent upon which it arises. When consciousness arises dependent on
the eye and forms, it is reckoned as eye-consciousness; when
consciousness arises dependent on the ear and sounds, it is reckoned
as ear-consciousness; when consciousness arises dependent on the nose
and odours, it is reckoned as nose-consciousness; when consciousness
arises dependent on the tongue and flavours, it is reckoned as
tongue-consciousness; when consciousness arises dependent on the body
and tangibles, it is reckoned as body-consciousness; when
consciousness arises dependent on the mind and mind-objects, it is
reckoned as mind-consciousness. Just as fire is reckoned by the
particular condition dependent on which it burns—when fire burns
dependent on logs, it is reckoned as a log fire; when fire burns
dependent on faggots, it is reckoned as a faggot fire; when fire burns
dependent on grass, it is reckoned as a grass fire; when fire burns
dependent on cowdung, it is reckoned as a cowdung fire; when fire
burns dependent on chaff, it is reckoned as a chaff fire; when fire
burns dependent on rubbish, it is reckoned as a rubbish fire—so too,
consciousness is reckoned by the particular condition dependent on
which it arises. When consciousness arises dependent on the eye and
forms, it is reckoned as eye-consciousness…when consciousness arises
dependent on the mind and mind-objects, it is reckoned as
mind-consciousness.
Think about it. How can the silent witness witness anything except through one of these media: eye, ear, nose, tongue, touch or mind? There was never a time, when there was consciousness being aware of something except through the eye, ear, nose, tongue, touch or mind. There is therefore no independent consciousness.
Consciousness is dependent on and conditioned upon these six media. It does not exist independently connecting all beings. The consciousness in every being may be of a similar type, but it's not the same consciousness.
For example, I can say that every candle has a similar flame, but it's not the exact same flame that appears on every candle. Each flame is different.
This is the only consciousness that there is, in the original teachings of the Buddha. There's no super consciousness or higher consciousness.
Also from the same sutta (MN 38):
The Blessed One then asked him: “Sāti, is it true that the following
pernicious view has arisen in you: ‘As I understand the Dhamma taught
by the Blessed One, it is this same consciousness that runs and
wanders through the round of rebirths, not another’?”
“Exactly so, venerable sir. As I understand the Dhamma taught by the
Blessed One, it is this same consciousness that runs and wanders
through the round of rebirths, not another.”
“What is that consciousness, Sāti?”
“Venerable sir, it is that which speaks and feels and experiences here
and there the result of good and bad actions.”
“Misguided man, to whom have you ever known me to teach the Dhamma in
that way? Misguided man, have I not stated in many ways consciousness
to be dependently arisen, since without a condition there is no
origination of consciousness? But you, misguided man, have
misrepresented us by your wrong grasp and injured yourself and stored
up much demerit; for this will lead to your harm and suffering for a
long time.”
The Buddha states unequivocally that consciousness is dependently originated based on conditions. There is no independent standalone permanent consciousness. There's no super consciousness or higher consciousness.
Some people claimed that MN 49 talks about a super consciousness or infinite consciousness, but that turned out to be a mistranslation. The sutta was talking about Nirvana or Nibbana - please see this answer.
From The All Sutta (also see this question):
"Monks, I will teach you the All. Listen & pay close attention. I will
speak."
"As you say, lord," the monks responded.
The Blessed One said, "What is the All? Simply the eye & forms, ear &
sounds, nose & aromas, tongue & flavors, body & tactile sensations,
intellect & ideas. This, monks, is called the All. Anyone who would
say, 'Repudiating this All, I will describe another,' if questioned on
what exactly might be the grounds for his statement, would be unable
to explain, and furthermore, would be put to grief. Why? Because it
lies beyond range.
Once again, there's no super consciousness or higher consciousness, outside the range of The All.
Now, what is shunya or shunyata (emptiness or void)? This is not a state of attainment or state of consciousness or state of reality or state of mind in Buddhism.
This is a statement of the fact of reality, by the Buddha in SN 35.85:
Then Ven. Ananda went to the Blessed One and on arrival, having bowed
down to him, sat to one side. As he was sitting there he said to the
Blessed One, "It is said that the world is empty, the world is empty,
lord. In what respect is it said that the world is empty?"
"Insofar as it is empty of a self or of anything pertaining to a self:
Thus it is said, Ananda, that the world is empty. And what is empty of
a self or of anything pertaining to a self? The eye is empty of a self
or of anything pertaining to a self. Forms... Eye-consciousness...
Eye-contact is empty of a self or of anything pertaining to a self.
"The ear is empty...
"The nose is empty...
"The tongue is empty...
"The body is empty...
"The intellect is empty of a self or of anything pertaining to a self.
Ideas... Intellect-consciousness... Intellect-contact is empty of a
self or of anything pertaining to a self. Thus it is said that the
world is empty."
This is a statement of the fact of reality that absolutely everything is empty of a self (Atman).
Now, what about that which is experienced?
We can talk about two different things which are experienced. One is Nirvana or Nibbana. This can be experienced by the Arahat (one who has become enlightened or awakened, or one who has become liberated from suffering) even outside of meditation.
Nibbana is described in this answer - please see that answer for sutta quotes:
Nibbana is not a thought of the mind, not a concept of the mind,
not a state of the mind, not a state of consciousness and also not a
feeling. However, when the mind experiences this Nibbana, which is not
conditioned, not compounded, not suffering, not impermanent, not
arising, not ceasing and not changing, it experiences bliss. The mind
can therefore experience Nibbana, but it cannot feel it or think about
it.
Sukha or happiness for an unenlightened person is experienced when
encountering pleasant feelings (from the six senses) or when
encountering the cessation of painful feelings (from the six senses).
But for an arahat, sukha or bliss (in this context) is experienced
when encountering neutral feelings, no feelings and Nibbana.
That is Nibbana, and not god or Brahman or any kind of Ultimate Reality. It is that which is experienced by the mind, when it is completely free of all fetters and defilements.
The second is nirodha samapatti. This is the state beyond the 8 jhana states. This is described on this page:
'attainment of extinction' (S. XIV, 11), also called
saññā-vedayita-nirodha, 'extinction of feeling and perception', is the
temporary suspension of all consciousness and mental activity,
following immediately upon the semi-conscious state called 'sphere of
neither-perception-nor-non-perception' (s. jhāna, 8). The absolutely
necessary pre-conditions to its attainment are said to be perfect
mastery of all the 8 absorptions (jhāna), as well as the previous
attainment of Anāgāmī or Arahantship (s. ariya-puggala).
According to Vis.M. XXIII, the entering into this state takes place in
the following way: by means of mental tranquillity (samatha) and
insight (vipassanā) one has to pass through all the 8 absorptions one
after the other up to the sphere of
neither-perception-nor-non-perception and then one has to bring this
state to an end. If, namely, according to the Vis.M., the disciple
(Anāgāmī or Arahat) passes through the absorption merely by means of
tranquillity, i.e. concentration, he will only attain the sphere of
neither-perception-nor-non-perception, and then come to a standstill;
if, on the other hand, he proceeds only with insight, he will reach
the fruition (phala) of Anāgāmī or Arahantship. He, however, who by
means of both faculties has risen from absorption to absorption and,
having made the necessary preparations, brings the sphere of
neither-perception-nor-non-perception to an end, such a one reaches
the state of extinction. Whilst the disciple is passing through the 8
absorptions, he each time emerges from the absorption attained, and
regards with his insight all the mental phenomena constituting that
special absorption, as impermanent, miserable and impersonal. Then he
again enters the next higher absorption, and thus, after each
absorption practising insight, he at last reaches the state of
neither-perception-nor-non-perception, and thereafter the full
extinction. This state, according to the Com., may last for 7 days or
even longer. Immediately at the rising from this state, however, there
arises in the Anāgāmī the fruition of Anāgāmiship (anāgāmi-phala), in
the Arahat the fruition of Arahantship (arahatta-phala).
With regard to the difference existing between the monk abiding in
this state of extinction on the one hand, and a dead person on the
other hand, M 43 says: "In him who is dead, and whose life has come to
an end, the bodily (in-and-out breathing), verbal (thought-conception
and discursive thinking), and mental functions (s. sankhāra, 2) have
become suspended and come to a standstill, life is exhausted, the
vital heat extinguished, the faculties are destroyed. Also in the monk
who has reached 'extinction of perception and feeling'
(saññā-vedayita-nirodha), the bodily, verbal and mental functions have
been suspended and come to a standstill, but life is not exhausted,
the vital heat not extinguished, and the faculties are not destroyed."
So, the question comes, who or what experiences nirodha samapatti?
The answer is no one and nothing. Why?
If all feeling, perception and consciousness is temporarily suspended, then it is not felt or perceived at all.
The Hindu notion of feeling stillness and bliss in meditation, applies to one or more of the conscious and semi-conscious states of jhana which are below nirodha samapatti. There are 8 such jhana (or dhyana) states explained in the suttas - 4 lower jhanas called rupa jhanas (or material jhanas) and 4 higher jhanas called arupa jhanas (or immaterial jhanas).
The 4 higher jhanas are the base of boundless space, the base of boundless consciousness, the base of nothingness, and the base of neither-perception-nor-non-perception (see this essay). I speculate that the perception of all-pervading consciousness mentioned in Vedanta, is probably experienced in the 6th of the 8 jhanas - called the base of boundless consciousness. I also speculate that the perception of voidness may be experienced in the 7th of the 8 jhanas - called the base of nothingness. This is a semi-conscious state.
Ruslan is also right that according to the Buddha, "there are no contemplatives outside of the Buddha's path" (Dhammapada 254-255). In my opinion, this is because in other paths, the practitioners are not free from self-view or belief in a self (sakkaya-ditthi), which is one of the ten fetters (AN 10.13).