“In the conditioned state, we are bewildered in our understanding, but in the perfect stage of liberation we can understand that Krishna is the cause of everything.”
This is from the Srimad-Bhagavatam 7.15.57
[In this chapter of the Srimad-Bhagavatam, entitled “Instructions for Civilized Human Beings,” the sage Narada tells King Yudhisthira about one process for attaining spiritual perfection.]
He who exists internally and externally, at the beginning and end of everything and of all living beings, as that which is enjoyable and as the enjoyer of everything, superior and inferior, is the Supreme Truth. He always exists as knowledge and the object of knowledge, as expression and the object of understanding, as darkness and as light. Thus He, the Supreme Lord, is everything.
Here the Vedic aphorism sarvam khalv idam brahma is explained. It is also explained in the catuh-sloki Bhagavatam. Aham evasam evagre. The Supreme Lord existed in the beginning, He exists after the creation and maintains everything, and after destruction everything merges in Him, as stated in Bhagavad-gita (prakrtim yanti mamikam). Thus the Supreme Lord is actually everything. In the conditioned state, we are bewildered in our understanding, but in the perfect stage of liberation we can understand that Krishna is the cause of everything.
isvarah paramah krsnah
anadir adir govindah
“Krishna, who is known as Govinda, is the supreme controller. He has an eternal, blissful, spiritual body. He is the origin of all. He has no other origin, for He is the prime cause of all causes.” (Brahma-samhita 5.1) This is the perfection of knowledge.