I am the controller of all

Yamarāja continues with the nature of ātmā in the next mantra.

eko vaśī sarvabhūtāntarātmā ekam rūpam bahudhā yaḥ karoti |

tamātmastham ye'nupaśyanti dhīrāsteṣām sukham śāśvatam netareṣām ||2-2-12||

The non-dual ātmā, as the inner controller of all beings, remains in one form while manifesting in manifold forms. The discriminative ones who see that ātmā dwells in the body enjoy eternal happiness; not the others.

ekaḥ - the one non-dual ātmā, sarvabhūtāntarātmā - who is the innermost self of all beings, vaśī - is the controller.  How does the innermost self become the controller?

ekam rūpam bahudhā yaḥ karoti - because one ātmā, by its mere existence (without any external factors) manifests into the manifold forms of the universe, as the satyam upon which the mithyā world depends on for its existence. Remaining in its own changeless, non-dual and indivisible nature, existence appears plural because of many bodies, yet not affected by them. Just as one existent dreamer manifests into many dream objects for transactions in the dream. Dream transactions can affect the dreamer who doesn’t know that the truth of the dream is himself alone. However, upon wakening, when he knows that everything is him alone, whatever happened in the dream does not affect him, because mithyā can’t affect satyam. tamātmastham ye'nupaśyanti dhīrāḥ - the discriminative ones recognise the fact that the controller of the whole world is the self alone, upon whom everything depends on, yet who does not depend on them, teṣām sukham śāśvatam - permanent happiness, which is the nature of the self, is available for them to appreciate. This happiness netareṣām - is not available for others whose minds are attached to the external objects because of identification. Although permanent happiness is their very self alone, it is obstructed by ignorance.

Next, yamarāja summed up the sat-cit-ānanda nature of ātmā.

nityo'nityānām cetanaścetanānām eko bahūnām yo vidadhāti kāmān |

tamātmastham ye'nupaśyanti dhīrāḥ teṣām śāntiḥ śāśvatī netareṣām ||2-2-13||

Ātmā is the permanent among the impermanent. It is the consciousness among conscious beings. Remaining one alone, it fulfils the desires of all. The discriminative ones who see that (ātmā) dwells in the body enjoy eternal peace; not the others.

nityo'nityānām - ātmā is the only permanent amidst all the impermanent things. Ātmā is permanent existence (satyam), the basis for impermanent names and forms (mithyā) to be there. cetanaścetanānām - ātmā is the consciousness among all conscious beings. The immortal consciousness illumines as the reflected consciousness in every inch of this mortal body. eko bahūnām yo vidadhāti kāmān - ātmā remains one, fulfills the various desires of all people. There is no single thing in the world can fulfill the diverse desires of all people. Unless the nature of the inner self is ānanda alone; otherwise, it would not be possible for us to be happy.

tamātmastham ye'nupaśyanti dhīrāḥ - the discriminative one recognises the fact that ones’s nature is sat-cit-ānanda. teṣām śāntiḥ śāśvatī - permanent peace is available for him, netareṣām - not for others.