Srimad Bhagavatham : 6.3.16.
Skandham-6 Chapter-3. Slokam-16. yam vai na gobhir manasasubhir va hrda gira vasu-bhrto vicaksate atmanam antar-hrdi santam atmanam cakshur yathaivakrtayas tatah param. yam = whom; vai = indeed; na = not; gobhih = by the senses; manasa = by the mind; asubhih = by the life breath; va = or; hrda = by thoughts; gira = by words; va = or; asu-bhrtah = the living entities; vicaksate = see or know; atmanam = the Supersoul; antah-hrdi = within the core of the heart; santam = existing; atmanam = of the living entities; caksuh = the eyes; yatha = just like; eva = indeed; akrtayah = the different parts or limbs of the body; tatah = than them; param = higher. As the different limbs of the body cannot see the eyes, the living entities cannot see the Supreme Lord, who is situated as the Supersoul