Bhagavad Gita Chapter 06, Text 31

Bg 6.31

sarva-bhuta-sthitam yo mam
bhajaty ekatvam asthitah
sarvatha vartamano ’pi
sa yogi mayi vartate

Word for word: 
sarva-bhuta-sthitam — situated in everyone’s heart; yah — he who; mam — Me; bhajati — serves in devotional service; ekatvam — in oneness; asthitah — situated; sarvatha — in all respects; vartamanah — being situated; api — in spite of; sah — he; yogi — the transcendentalist; mayi — in Me; vartate — remains.

Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Such a yogi, who engages in the worshipful service of the Supersoul, knowing that I and the Supersoul are one, remains always in Me in all circumstances.

Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
A yogi who is practicing meditation on the Supersoul sees within himself the plenary portion of Krishna as Visnu – with four hands, holding conchshell, wheel, club and lotus flower. The yogi should know that Visnu is not different from Krishna. Krishna in this form of Supersoul is situated in everyone’s heart. Furthermore, there is no difference between the innumerable Supersouls present in the innumerable hearts of living entities. Nor is there a difference between a Krishna conscious person always engaged in the transcendental loving service of Krishna and a perfect yogi engaged in meditation on the Supersoul. The yogi in Krishna consciousness – even though he may be engaged in various activities while in material existence – remains always situated in Krishna. This is confirmed in the Bhakti-rasamrta-sindhu (1.2.187) of Srila Rupa Gosvami: nikhilasv apy avasthasu jivan-muktah sa ucyate. A devotee of the Lord, always acting in Krishna consciousness, is automatically liberated. In the Narada Pañcaratra this is confirmed in this way:

krsne ceto vidhaya ca
tan-mayo bhavati ksipram
jivo brahmani yojayet

“By concentrating one’s attention on the transcendental form of Krishna, who is all-pervading and beyond time and space, one becomes absorbed in thinking of Krishna and then attains the happy state of transcendental association with Him.”

Krishna consciousness is the highest stage of trance in yoga practice. This very understanding that Krishna is present as Paramatma in everyone’s heart makes the yogi faultless. The Vedas (Gopala-tapani Upanisad 1.21) confirm this inconceivable potency of the Lord as follows: eko ’pi san bahudha yo ’vabhati. “Although the Lord is one, He is present in innumerable hearts as many.” Similarly, in the smrti-sastra it is said:

eka eva paro visnuh
sarva-vyapi na samsayah
aisvaryad rupam ekam ca
surya-vat bahudheyate

“Visnu is one, and yet He is certainly all-pervading. By His inconceivable potency, in spite of His one form, He is present everywhere, as the sun appears in many places at once.”