One is in jhana when the hindrances are absent and when the Enlightenment Factors are present to some degree. For example, in the first and second jhana, there is present Joy. In the third and fourth jhana, there are more prevalent the factors of Equanimity and Tranquility. But in all jhanas, there is always present Mindfulness, Collectedness, Enthusiasm, and Investigation. As one reaches the arupa jhanas, these Factors become more refined and more balanced.
In terms of conceit, being, ignorance and delusion, they will be present insofar as one considers a sense of self to any of these factors. However, that does not make the jhana unwholesome or ineffective. It is the insight of this, that arises from jhana itself.
Let’s break it down in the context of kamma. There is the wholesome kamma and the unwholesome kamma. At the mundane level of the Eightfold Path, one endeavors to scale up from the unwholesome kamma to the wholesome kamma. But even wholesome kamma creates an effect. It is a good effect, but nonetheless an effect that causes rebirth. This is because there is still Bhava – sense of being there – due to clinging to the factors of jhana, which can cause rebirth in the Formless Realms.
However, once one sees through this, letting go of conceit, then such activity of entering jhana, and other activities in general, do not produce more seeds of rebirth. Such activities are non-abiding or unconditioned, or simply understood as wholly impersonal. They can be labeled neutral to the extent that there is no sense of doer, or being, in those activities. Then one is functioning at the supramundane level of the Eightfold Path. Through such jhana practice, there is no sense of a meditator – just the meditating happening as an impersonal activity.
In short, so long as one is not absorbed and the enlightenment Factors are present, such jhana is wholesome, with potential to create positive states of existence.
When the arahant meditates, such jhana is also wholesome, but without the potential to create any state of existence.
If one is to extend this understanding towards the levels of awakening, it can be understood in this way:
For a worldling, they may produce wholesome actions, but without Right View, they have the potential of lower rebirths.
The Sotapanna [Stream-enterer], has Mundane Right View and has eradicated Doubt, Attachment to Self-Views and Attachment to Rites and Rituals, so they produce wholesome actions as well. Their future states of existence, if not having crossed further, will be in a human realm or higher, within the sensual planes of existence.
The Sakadagami [Once-Returner], has further reduced Craving and Ill Will. But since these are still present, if not having crossed further, they will also take rebirth in a human realm or higher, within the sensual planes of existence.
The Anagami [Non-Returner], has eradicated Craving and Ill Will. But because they still have Ignorance, Conceit, Restlessness, Craving for Existence and Non-Existence, while their actions are wholesome, and because they still have tendencies towards Conceit, Being and Ignorance, they will take rebirth beyond the sensual realms, into the Pure Abodes.
An Anagami may cling to the jhanas, but not because of Mentality attaching Being to the relief. Rather their clinging is to the Dhamma itself, and because jhana is contained within the Dhamma, there is relishing for that sake, not for the mental relief itself. Thus, the Formations that arise are void of the craving arising because of the feelings from jhana, but they are still fettered by identifying with the jhana, and by extension the Dhamma.
For the Arahant, because they have let go of all tendencies and fetters and defilements, no more potential for rebirth arises. Even if they produce wholesome actions, such actions don’t arise from a mentality that is rooted in Conceit or sense of doer.
In short, one is to understand that wholesome activities produce wholesome effects (and rebirths) only if they contain the sense of Being and self in them. Only at the level of Arahantship, the tendencies of conceit, being, and ignorance are fully destroyed, so any wholesome action taken is considered fruit-less, unable to produce any further new kamma.
This is why it is recommended that
1) one doesn’t get absorbed in jhana [one-pointed concentration] because then, while no hindrances are present, no Factors of Awakening are present either. Or if they are, they are not observed and developed in a fruitful and effective manner.
2) one doesn’t cling to jhana with a sense of self so that no Formations, rooted in the mental craving for jhana, can become strengthened and create the possibility of rebirth in a jhanic realm. Beyond this, no Formations rooted in the identifying with the Dhamma will arise either.
The more one understands this, and the more one enters jhana without grasping and clinging, the more one wears away the fetters, Formations and tendencies. Because these would cause rebirths, related to that jhana that is being clung to. Or to the Dhamma itself, which causes rebirth in the Pure Abodes, which in turn leads one closer to Arahantship.