SB 8.12.11
sa tvam samihitam adah sthiti-janma-nasam
bhutehitam ca jagato bhava-bandha-moksau
vayur yatha visati kham ca caracarakhyam
sarvam tad-atmakatayavagamo ’varuntse
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
My Lord, You are the supreme knowledge personified. You know everything about this creation and its beginning, maintenance and annihilation, and You know all the endeavors made by the living entities, by which they are either implicated in this material world or liberated from it. As the air enters the vast sky and also enters the bodies of all moving and nonmoving entities, You are present everywhere, and therefore You are the knower of all.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
As stated in the Brahma-samhita:
eko ’py asau racayitum jagad-anda-kotim
yac-chaktir asti jagad-anda-caya yad-antah
andantara-stha-paramanu-cayantara-stham
govindam adi-purusam tam aham bhajami
“I worship the Personality of Godhead, Govinda, who by one of His plenary portions enters the existence of every universe and every atomic particle and thus manifests His infinite energy unlimitedly throughout the material creation.” (Brahma-samhita 5.35)
ananda-cinmaya-rasa-pratibhavitabhis
tabhir ya eva nija-rupataya kalabhih
goloka eva nivasaty akhilatma-bhuto
govindam adi-purusam tam aham bhajami
“I worship Govinda, the primeval Lord, who resides in His own realm, Goloka, with Radha, who resembles His own spiritual figure and who embodies the ecstatic potency [hladini]. Their companions are Her confidantes, who embody extensions of Her bodily form and who are imbued and permeated with ever-blissful spiritual rasa.” (Brahma-samhita 5.37)
Although Govinda is always present in His abode (goloka eva nivasati), He is simultaneously present everywhere. Nothing is unknown to Him, and nothing can be hidden from Him. The example given here compares the Lord to the air, which is within the vast sky and within every body but still is different from everything.