One verse

Srimad Bhagavatam 11.17.32

11.17.32

अग्नौ गुरावात्मनि च सर्वभूतेषु मां परम् । अपृथग्धीरुपासीत ब्रह्मवर्चस्व्यकल्मष: ॥ ३२ ॥

agnau gurāv ātmani ca sarva-bhūteṣu māṁ param apṛthag-dhīr upasīta brahma-varcasvy akalmaṣaḥ

agnau
in fire
gurau
in the spiritual master
ātmani
in oneself
ca
also
sarva-bhūteṣu
in all living entities
mām
Me
param
the Supreme
apṛthak-dhīḥ
without any concept of duality
upāsīta
one should worship
brahma-varcasvī
possessing Vedic enlightenment
akalmaṣaḥ
sinless

Thus enlightened in Vedic knowledge by service to the spiritual master, freed from all sins and duality, one should worship Me as the Supersoul, as I appear within fire, the spiritual master, one’s own self and all living entities.