Srimad Bhagavatam Canto 10, Chapter 63, Text 34

SB 10.63.34

sri-rudra uvaca
tvam hi brahma param jyotir
 gudham brahmani van-maye
yam pasyanty amalatmana
 akasam iva kevalam
Sri Rudra said: You alone are the Absolute Truth, the supreme light, the mystery hidden within the verbal manifestation of the Absolute. Those whose hearts are spotless can see You, for You are uncontaminated, like the sky.
The Absolute Truth is the source of all light and is therefore the supreme light, self-luminous. This Absolute Truth is explained confidentially in the Vedas and is therefore difficult for an ordinary reader to understand. The following statements quoted by Srila Jiva Gosvami from the Gopala-tapani Upanisad show how the Vedic sounds occasionally reveal the Absolute: Te hocur upasanam etasya paratmano govindasyakhiladharino bruhi (Purva-khanda 17): “They [the four Kumaras] said [to Brahma], ‘Please tell us how to worship Govinda, the Supreme Soul and the foundation of all that exists.’” Cetanas cetananam (Purva-khanda 21): “He is the chief of all living beings.” And tam ha devam atma-vrtti-prakasam (Purva-khanda 23): “One realizes that Supreme Godhead by first realizing one’s own self.” The great acarya Jiva Gosvami also quotes a verse from the Srimad-Bhagavatam (7.10.48) — gudham param brahma manusya-lingam — which refers to “the Supreme Truth concealed in a humanlike form.”
Since the Lord is pure, why do some people perceive Krsna’s form and activities as impure? Acarya Jiva explains that those whose own hearts are impure cannot understand the pure Lord. Srila Visvanatha Cakravarti further quotes the Lord’s own instruction to Arjuna in Sri Hari-vamsa:
tat-param paramam brahma
 sarvam vibhajate jagat
mamaiva tad ghanam tejo
 jñatum arhasi bharata
“Superior to that [total material nature] is the Supreme Brahman, from which this entire creation expands. O descendant of Bharata, you should know that the Supreme Brahman consists of My concentrated effulgence.”
Thus, to save his devotee, Siva now glorifies the Supreme Lord, Krsna, his eternal worshipable master. The Lord’s bewildering potency induced Siva to fight with Lord Krsna, but now the fight is over, and to save his devotee Lord Siva offers these beautiful prayers.
Srimad Bhagavatam Canto 10, Chapter 63, Text 33
Srimad Bhagavatam Canto 10, Chapter 63, Text 35-36