sarvabhootasthitam yo maam bhajatyekatvamaastitaha |
sarvathaa vartamaanopi sa yogi mayi vartate || 31 ||

Established in oneness with me, one who beholds me as present in all beings, that yogi resides within me, in all circumstances.
sarvabhootasthitam : present in all beings
yaha : one who
maam : me
bhajati : beholds
ekatvam : oneness
aastitaha : established
sarvathaa : all
vartamaanaha : circumstances
sa : that
yogi : yogi
maiyi : within me
vartate : resides
In order to emphasize the oneness of the individual with the absolute, Shri Krishna says that the yogi who sees him present in all beings is always residing in him, no matter what circumstance the yogi finds himself in. In other words, the devotee does not lose his connection with Ishvara in any and all worldly and spiritual pursuits.
First, let us refer back to our wave and ocean example to understand what is meant by “ekatvam” or oneness. If the wave sees himself as part of the ocean, and also sees the other waves as part of the ocean, it ultimately realizes that everything is the ocean. It realizes that there is no separation of wave and ocean, and in doing so, attains oneness with the ocean. Similarly, Shri Krishna says that the yogi who sees all beings in Ishvara, discards any thought of separation from Ishvara. He thus attains oneness with Ishvara.
Here is another example. Let us say that we attend a cricket match where India is playing against some other team. If we sit alongside the Indian team fans, there is no way we can ever forget the India team. Why? Someone will have the Indian team logo on their shirt or on their cap. Someone will be chanting the player’s names. Someone will be holding up cardboard signs. No matter where we look or what we hear, it will be something about the India team. We will see the India team spirit in everyone. There will be no thought of separation from the India team.
Furthermore, Shri Krishna says that the yogi never loses this oneness, it stays with him no matter what transaction he conducts in this world. Many of us have a hands-free headset that lets us stay connected on a phone call regardless of whether we are walking, climbing stairs, shopping and so on. The yogi thus maintains an “always-on” connection with Ishvara. The yogi does not need to go on a pilgrimage or visit any specific temple, because he is always connected to Ishvara.
Now, this does not mean that going to temples or pilgrimages is not encouraged. These places create a conducive environment for the seeker to focus his thoughts on Ishvara, which definitely accelerates the spiritual progress. But the notion that “Ishvara is in this object, and nowhere else” is incorrect, it should be discarded.
In his commentary, Shri Shankaraachaaryaji says that for such a yogi, there is nothing that can obstruct his liberation or moksha. He is ever-liberated or nitya-mukta, because he knows that he was never bound in the first place.