Trinity exists in nature as well as in Spirituality.
Everything moves in a cycle, in three steps; from formless to form and then back to formless.
Desire – Object - Satisfaction (Or Anger and Frustration in case of failure to get it)
For example, Hunger is formless, but to satisfy the hunger, we need food that is in some kind of form. Ultimately that food turns into formless energy.
Hunger – Food – Energy
(Formless – Form – Formless)
Similarly, we as ‘Atman’ are formless. We take on a physical form and then, after leaving the body, turn into formless again.
But the cycle never ends. Just like we get hungry again and consume more food, similarly when the Kaamna, (desire) arises, we take up another body, another physical form and the cycle continues.
To end this cycle, Holy Scriptures define another Trinity; a similar three step process.
Jigyaasa – Guru – Gyana
Jigyaasa, the desire (to know the Self) is formless.
Through the Guru, a physical form, we can achieve the Gyana which is formless.
Once the Gyana is achieved, to break the cycle of this ‘trinity’ of Formless to Form and again to Formless, one needs to move on to the next step; next Trinity. That is:
Gyana – Dhyana – Moksha (Gyana, Meditation, Freedom)
Now, as we can see, these all three are formless.
Previously, the original trinity of existence consisted of:
Aatma – Shareer – Parmaatma (Soul – Body - Super Soul)
When we rise above the boundaries of Naam-Roop; the ‘name and form’, when the Shareer, the middle of this trinity is dissolved, not by death, but through Gyana, Realization, then only two Formless entities remain.
Aatma – Parmaatma that is Soul and Super-soul.
Moksha is freedom from the form.
Now, since there is no dividing ‘Form’ between the two, both the Formless merge into one and the cycle breaks.
But as long as there is ‘Desire’ and ‘Kartaa-Bhaava, the sense of ‘Doer-ship’, the cycle may not break.
Just like if hunger is there, we start craving and searching for food.
If Desire and Kartaa-Bhava still remains, then the Aatma strives to get another body to fulfil the unfulfilled desires and the cycle starts all over again.