Īśāvāsyopaniṣat 07
He who understands that ātman , in whom all beings exist and in whom alone they take shelter, who perceives that one lord (principle) in all beings, for such a person where is delusion? where is grief?
Īśā.Bhāshya 07
The verse conveys the omnipresent attribute of the lord. A reference is given to Pippalāda vedic testimonial, where the concept is reiterated, providing the hermeneutical context.
In which supreme being exists all beings, he is the supreme lord. There, all beings existed even before. Thus, for one who knows that the supreme lord resides uniformly in all beings, where is delusion?
"In whom all beings exist, He is the 'atman' of all beings. Thus, whoever perceives Vishnu everywhere, really knows Him. What delusion or grief can there be for him? He attains Vishnu."
- stated thus in the Pippalāda vedic testimonial.
As per the earlier explained translation, absence of grief and delusion indicates the correct understanding. By practicing (i.e. by perceiving the presence of the lord in all beings), the omnipresent attribute of the lord comes to light.