In Srimad Bhagavad-gita (10.8) Sri Krishna explains that He is the source of all spiritual and material worlds. "Everything emanates from Me. The wise who know this perfectly engage in My devotional service and worship Me with all their hearts."
Bhagavan Krishna further relates that all other sages and creators also originate from Him: "The seven great sages and before them the four other great sages and the Manus [progenitors of mankind] are born out of My mind, and all creatures in these planets descend from them." (Bg.10.6)
Jambavan also says to Bhagavan Krishna, "You are the ultimate creator of all creators of the universe, and of everything created You are the underlying substance. You are the subduer of all subduers, the Supreme Bhagavan and Supreme Soul of all souls." (Bhag.10.56. 27)
When the Devas approached Bhagavan Krishna to return to His eternal abode and wind up His earthly pastimes, they also recognized that He was the supreme God in their prayers : "You are the cause of the creation, maintenance and destruction of this universe. As time, You regulate the subtle and manifest states of material nature and control every living being. As the threefold wheel of time You diminish all things by Your imperceptible actions, and thus You are the Supreme Personality of Godhead... O Bhagavan, You are the supreme creator of this universe and the ultimate controller of all moving and nonmoving living entities. You are Hrishikesha, the supreme controller of all sensory activity, and thus You never become contaminated or entangled in the course of Your supervision of the infinite sensory activities within the material creation. On the other hand, other living entities, even yogis and philosophers, are disturbed and frightened simply by remembering the material objects that they have supposedly renounced in their pursuit of enlightenment. " (Bhag.11.6.15, 17)
Because Sri Krishna is the source of everything, it is not possible for others to determine His origin. "Neither the hosts of Devas nor the great Sages know My origin, for, in every respect, I am the source of the Devas and Sages." (Bg.10.2)
Arjuna also admits to this fact after having understood Krishna 's real characteristics: "O Krishna, I totally accept as truth all that You have told me. Neither the gods nor demons, O Bhagavan, know Thy personality. Indeed, You alone know Yourself by Your own potencies, O origin of all, Bhagavan of all beings, God of Gods, O Supreme Person, Bhagavan of the universe! (Bg.10.14-15) O great one, who stands above even Brahma, You are the original master. Why should they not offer their homage up to You, O limitless one? O refuge of the universe, You are the invincible source, the cause of all causes, transcendental to this material manifestation. (Bg.11.37) You are air, fire, water, and You are the moon! You are the supreme controller and the grandfather. Thus I offer my respectful obeisances unto You a thousand times, and again and yet again! Obeisances from the front, from behind and from all sides! O unbounded power, You are the master of limitless light! You are all-pervading, and thus You are everything! (Bg.11.39-40) You are the father of this complete cosmic manifestation, the worshipable chief, the spiritual master. No one is equal to You, nor can anyone be one with You. Within the three worlds, You are immeasurable. " (Bg.11.43)
Even the immeasurable spiritual entity called the Brahman is actually a tool that Krishna uses in which to create the cosmic manifestation. As Bhagavan explains, "The total material substance, called Brahman, is the source of birth, and it is that Brahman that I impregnate, making possible the births of all living beings, O son of Bharata [Arjuna]. It should be understood that all species of life, O son of Kunti, are made possible by birth in this material nature, and that I am the seed-giving father. (Bg.14.3-4) Of all that is material and all that is spiritual in this world, know for certain that I am both its origin and dissolution. (Bg.7.6) I am the generating seed of all existences. There is no being--moving or unmoving--that can exist without Me. (Bg.10.39) Know that I am the original seed of all existences, the intelligence of the intelligent, and the prowess of all powerful men." (Bg.7.10)
In this way, Bhagavan Krishna creates the material manifestation, and later absorbs it back into Himself. Then at His will, He again creates. "At the end of the millennium every material manifestation enters into My nature, and at the beginning of another millennium, by My potency I again create." (Bg.9.7)
"My dear Bhagavan, the original purusha-avatara, Maha-Vishnu, acquires His creative potency from You. Thus with infallible energy He impregnates material nature, producing the mahat-tattva. Then the mahat-tattva, the amalgamated material energy, endowed with the potency of the Bhagavan, produces from itself the primeval golden egg of the universe, which is covered by various layers of material elements." (Bhag.11.6.16)
Because Bhagavan Krishna is the source of everything, there is obviously nothing that He personally needs from it, nor is He ever entangled in it. He is like the warden of a prison who can go in or out of it at any time he wants. Yet He is still overseeing it. "O son of Pritha, there is no work prescribed for Me within all the three planetary systems. Nor am I in want of anything, nor have I need to obtain anything--and yet I am engaged in work. (Bg.3.22) There is no work that affects Me; nor do I aspire for the fruits of action. One who understands this truth about Me also does not become entangled in the fruitive reactions of work." (Bg.4.14)
Akrura also admitted to Bhagavan Krishna that, "You create, destroy and also maintain this universe with Your personal energies--the modes of passion, ignorance and goodness--yet You are never entangled by these modes or the activities they generate. Since You are the original source of all knowledge, what could ever cause You to be bound by illusion?" (Bhag.10.48. 21)
The summary process of how Bhagavan Krishna manifests and gives facility to the universe and the living entities within it is described in Vasudeva's prayer to Bhagavan Krishna: "O transcendental Bhagavan, from Yourself You created this entire variegated universe, and then You entered within it in Your personal form as the Supersoul. In this way, O unborn supreme Soul, as the life force and consciousness of everyone, You maintain the creation. Whatever potencies the life air and other elements of universal creation exhibit are actually all personal energies of the Supreme Bhagavan, for both life and matter are subordinate to Him and dependent on Him, and also different from one another. Thus, everything active in the material world is set into motion by the Supreme Bhagavan. The glow of the moon, the brilliance of fire, the radiance of the sun, the twinkling of the stars, the flash of lightning, the permanence of mountains and the aroma and sustaining power of the earth--all these are actually You. My Bhagavan, You are water, and also its taste and its capacities to quench thirst and sustain life. You exhibit Your potencies through the manifestations of the air as bodily warmth, vitality, mental power, physical strength, endeavor and movement. You are the directions and their accommodating capacity, the all-pervading ether and the elemental sound residing within it. You are the primeval, unmanifested form of sound; the first syllable, om: and audible speech, by which sound, as words, acquires particular references. You are the power of the senses to reveal their objects, the senses' presiding demigods, and the sanction these Devas give for sensory activity. You are the capacity of the intelligence for decision-making, and the living being's ability to remember things accurately. You are false ego in the mode of ignorance, which is the source of physical elements; false ego in the mode of passion, which is the source of the bodily senses; false ego in the mode of goodness, which is the source of the Devas; and the unmanifest, total material energy, which underlies everything. You are the indestructible entity among all the destructible things of this world, like the underlying substance that is seen to remain unchanged while the things made from it undergo transformation. " (Bhag.10.85. 5-12)
"Thus these created entities, transformations of material nature, do not exist except when material nature manifests them within You, at which time You also manifest within them. But aside from such periods of creation, You stand alone as the transcendental reality." (Bhag.10.85. 14)
Being the source of everything, Bhagavan Krishna explains how He is also the source of genuine religion. "The Supreme Personality of Godhead said : `O Brahmana, I am the speaker of religion, its performer and sanctifier. I observe religious principles to teach them to the world, My child, so do not be disturbed." (Bhag.10.69. 40)
Bhagavan Krishna goes on to say that the understanding of how He is the origination of everything is the knowledge which can free a person from sins: "He who knows Me as the unborn, as the beginningless, as the Supreme Bhagavan of all the worlds--he, undeluded among men, is freed from all sins." (Bg.10.3) This is the special nature of this spiritual knowledge.
Om Namo Bhagavate Vasudevaya !!!