The mere understanding that ‘there is no person’ is not by itself enough. The mere understanding/seeing or knowledge ‘there is no separation’, ‘there is no doer’, ‘there is no separate self’ is by itself not enough.
For suffering to end, the self-referential habitual tendencies (vasanas) which originally arose from the belief in separation, these vasanas must also end. These vasanas are those addictive tendencies which aim to seek fulfillment in experiences and things (ie. in objects).
Seeing ‘there’s nobody here’ is seeing through the illusion of separation. However the functioning of self-referential addictive vasanas may continue due to the deeply established force of habit, and so the suffering resulting from these on the phenomenal level continues.
Once the illusion of (separate) self is seen as an illusion*, one must still remove the vasanas**. How? We are advised simply to ‘be still’.
…one must still remove the vasanas. How? We are advised simple to ‘be still’.
There is an apparent contradiction here, for if the separate self is seen through and seen to be false, then who or what is being still? Well, when the vasanas arise, it is really the sense of/belief in separate self that arises, out of habit, which means that although the individual person has intellectually been seen to be non-existent, it is actually the person who knows this. The person is the ignorance, which means that the ignorance has not been fully rooted out. ie. ignorance is still present.
So, insight (into no-self) having been attained (in the mind), now we are advised to be still in order to purify our minds of the vasanas. Shankara famously wrote: vasana kshaya moksham, which means ‘destruction of the vasanas is Moksha (liberation).’
-Can the ego make the ego still?
-Can thought still thought?
-Can we become effortless through effort?
The answer is no. Knowing this, be still.
Allow what comes to come, allow what goes to go. See there is nobody here. As the vasanas/ego/sense of ‘me’ arise, allow them to fall again.
Note that being still is not doing something. It is not trying hard to be still – that is just more effort. Rather ‘be still’ means not adding to this, or rather to stop seeking and grasping, letting things be as they are, no longer looking for fulfillment in objects.
Being still is not doing something
The above reasoning and this last sadhana (spiritual practice) of stillness is beautifully expressed in the classic Advaita text Advaita Bodha Deepika, which was recommended by Ramana Maharshi as a manual for Advaita. The text takes the seeker through all aspects of the path. see here for a short excerpt:
Similarly in Buddhism and Zen we see the same teachings. See here for an example:
*traditionally the Vedanta path is threefold. Firstly the teachings are heard (sravana), then they are comtemplated upon (manana) and their truth is realised/ignorance is removed. Then lastly the vasanas or habitual tendencies which originally arose due to ignorance are purified (nididhyasana).
**Many people stop after manana, once the truth has been understood and realised (in the intellect). The scriptures warn us that whilst this realisation can bring great peace and relief, and can be mistaken for full realisation/enlightenment, this is not the end of the journey, for the belief in a jiva/limited entity is still intact. Even without trusting the scriptures, by simply being aware of and open to what is happening, it can be seen that unless the addictive self-referential vasanas are allowed to arise in stillness, then without being taken up and acted on, allowed to then dissolve and die, the self-created suffering and self-centred (potentially destructive) behaviours on the phenomenal experiential level continue. Being still is simply a natural way of allowing the ignorance-based conditioning to naturally arise and fall away of its own accord.