SB 6.4.30
yasmin yato yena ca yasya yasmai
yad yo yatha kurute karyate ca
paravaresam paramam prak prasiddham
tad brahma tad dhetur ananyad ekam
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The Supreme Brahman, Krsna, is the ultimate resting place and source of everything. Everything is done by Him, everything belongs to Him, and everything is offered to Him. He is the ultimate objective, and whether acting or causing others to act, He is the ultimate doer. There are many causes, high and low, but since He is the cause of all causes, He is well known as the Supreme Brahman who existed before all activities. He is one without a second and has no other cause. I therefore offer my respects unto Him.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The Supreme Personality of Godhead, Krsna, is the original cause, as confirmed in Bhagavad-gita (aham sarvasya prabhavah). Even this material world, which is conducted under the modes of material nature, is caused by the Supreme Personality of Godhead, who therefore also has an intimate relationship with the material world. If the material world were not a part of His body, the Supreme Lord, the supreme cause, would be incomplete. Therefore we hear, vasudevah sarvam iti sa mahatma su-durlabhah: if one knows that Vasudeva is the original cause of all causes, he becomes a perfect mahatma.
The Brahma-samhita (5.1) declares:
isvarah paramah krsnah
sac-cid-ananda-vigrahah
anadir adir govindah
sarva-karana-karanam
“Krsna, 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.” The Supreme Brahman (tad brahma) is the cause of all causes, but He has no cause. Anadir adir govindah sarva-karana-karanam: Govinda, Krsna, is the original cause of all causes, but He has no cause for His appearance as Govinda. Govinda expands in multifarious forms, but nevertheless they are one. As confirmed by Madhvacarya, ananyah sadrsabhavad eko rupady-abhedatah: Krsna has no cause nor any equal, and He is one because His various forms, as svamsa and vibhinnamsa, are nondifferent from Himself.