Brahmā, born out of the lotus flower, could not see the world, although he was situated in the whorl. He therefore circumambulated all of space, and while moving his eyes in all directions he achieved four heads in terms of the four directions."
(SRIMAD BHAGAVATAM------3:8:16------TRANSLATION).

It is also stated that this description is of only one egglike universe. There are innumerable universes besides this one, and some of them are many, many times greater. It is considered, in fact, that this universe is the smallest; therefore the predominating superintendent, or Brahmā, has only four heads for management. In other universes, which are far greater than this one, Brahmā has more heads. In the Caitanya-caritāmṛta it is stated that all these Brahmās were called one day by Lord Kṛṣṇa on the inquiry of the small Brahmā, who, after seeing all the larger Brahmās, was thunderstruck. That is the inconceivable potency of the Lord.
(SRIMAD BHAGAVATAM------3:26:52------PURPORT).

When Brahmā approached Kṛṣṇa, the doorman informed Kṛṣṇa that Brahmā had arrived to see Him. Upon hearing this, Kṛṣṇa inquired as to which Brahmā had come, and the doorman returned to Brahmā and asked, "Which Brahmā are you? Kṛṣṇa has asked."
Brahmā was struck with wonder. Why did Kṛṣṇa ask such a question? He informed the doorman, "Please tell Him that Brahmā, who is the father of the four Kumāras and who has four heads, has come to see Him."

The doorman informed Kṛṣṇa and then asked Brahmā inside. Brahmā offered his obeisances unto the lotus feet of Kṛṣṇa, and after receiving him with all honor, Kṛṣṇa inquired about the purpose of his visit.

"I shall tell You of my purpose in coming here," Lord Brahmā replied, "but first I have a doubt which I ask You to kindly remove. Your doorman told me that You asked which Brahmā has come to see You. May I inquire if there are other Brahmās besides me?"

Upon hearing this, Kṛṣṇa smiled and at once called for many Brahmās from many universes. The four-headed Brahmā then saw many other Brahmās coming to see Kṛṣṇa and to offer their respects. Some of them had ten heads, some had twenty, some had a hundred and some even had a million heads. Indeed, the four-headed Brahmā could not even count the Brahmās who were coming to offer their obeisances to Kṛṣṇa. Kṛṣṇa then called many other demigods from various universes, and they all came to offer their respects to the Lord. Upon seeing this wonderful exhibition, the four-headed Brahmā became nervous and began to think of himself as no more than a mosquito in the midst of many elephants.

(TEACHINGS OF LORD CAITANYA).

Anasūyā, the wife of Atri Muni, gave birth to three very famous sons—Soma, Dattātreya and Durvāsā—who were partial representations of Lord Viṣṇu, Lord Śiva and Lord Brahmā. Soma was a partial representation of Lord Brahmā, Dattātreya was a partial representation of Lord Viṣṇu, and Durvāsā was a partial representation of Lord Śiva.
In this verse we find the words ātma-īśa-brahma-sambhavān. Ātma means the Supersoul, or Viṣṇu, īśa means Lord Śiva, and brahma means the four-headed Lord Brahmā. The three sons born of Anasūyā—Dattātreya, Durvāsā and Soma—were born as partial representations of these three demigods. Ātma is not in the category of the demigods or living entities because He is Viṣṇu; therefore He is described as vibhinnāṁśa-bhūtānām. The Supersoul, Viṣṇu, is the seed-giving father of all living entities, including Brahmā and Lord Śiva. Another meaning of the word ātma may be accepted in this way: the principle who is the Supersoul in every ātma, or, one may say, the soul of everyone, became manifested as Dattātreya, because the word aṁśa, part and parcel, is used here.

(SRIMAD BHAGAVATAM------4:1:15------TRANSLATION AND PURPORT).

Since so many demigods were offering obeisances unto the lotus feet of Kṛṣṇa, Brahmā concluded that the unlimited potency of Kṛṣṇa could not be estimated. All the helmets of the various demigods and Brahmās shone brightly in the great assembly, and the prayers of the demigods made a great sound.
"Dear Lord," the demigods said, "it is Your great mercy that You have called us to see You. Is there any particular order? If so, we will carry it out at once."

"There is nothing especially required of you," Lord Kṛṣṇa replied. "I only wanted to see you together at one time. I offer My blessing to you. Don't fear the demons."

"By Your mercy, everything is all right," they all replied. "There are no disturbances at present, for by Your incarnation everything inauspicious is vanquished."

As each of the Brahmās saw Kṛṣṇa, each thought that He was only within his universe. After this incident, Kṛṣṇa wished all the Brahmās farewell, and after offering respects to Him, they returned to their respective universes. Upon seeing this, the four-headed Brahmā at once fell down at the feet of Kṛṣṇa and said, "What I thought about You at first was all nonsensical. Everyone may say that they know You in perfection, but as far as I am concerned, I cannot begin to conceive how great You are. You are beyond my conception and understanding."

(TEACHINGS OF LORD CAITANYA).

Lord Brahmā is described in this verse as the original cause of the cosmic manifestation, and this applies to his position in the material world. There are many, many such controllers, all of whom are created by the Supreme Lord, Viṣṇu. This is illustrated by an incident described in Caitanya-caritāmṛta. When the Brahmā of this particular universe was invited by Kṛṣṇa to Dvārakā, he thought that he was the only Brahmā. Therefore when Kṛṣṇa inquired from His servant which Brahmā was at the door to visit, Lord Brahmā was surprised. He replied that of course Lord Brahmā, the father of the four Kumāras, was waiting at the door. Later, Lord Brahmā asked Kṛṣṇa why He had inquired which Brahmā had come. He was then informed that there are millions of other Brahmās because there are millions of universes. Kṛṣṇa then called all the Brahmās, who immediately came to visit Him. The catur-mukha Brahmā, the four-headed Brahmā of this universe, thought himself a very insignificant creature in the presence of so many Brahmās with so many heads. Thus although there is a Brahmā who is the engineer of each universe, Kṛṣṇa is the original source of all of them.

(SRIMAD BHAGAVATAM------7:3:28------PURPORT).

The word nāthāḥ, which refers to Lord Brahmā, is plural because there are innumerable universes and innumerable Brahmās. Brahmā is but a tiny force. This was exhibited in Dvārakā when Kṛṣṇa called for Brahmā. One day when Brahmā came to see Kṛṣṇa at Dvārakā, the doorman, at Lord Kṛṣṇa's request, asked, "Which Brahmā are you?" Later, when Brahmā inquired from Kṛṣṇa whether this meant that there was more than one Brahmā, Kṛṣṇa smiled and at once called for many Brahmās from many universes. The four-headedBrahmā of this universe then saw innumerable other Brahmās coming to see Kṛṣṇa and offer their respects. Some of them had ten heads, some had twenty, some had a hundred and some had a million heads. Upon seeing this wonderful exhibition, the four-headed Brahmā became nervous and began to think of himself as no more than a mosquito in the midst of many elephants. Therefore, what can Brahmā do to bewilder Kṛṣṇa?

(SRIMAD BHAGAVATAM------10:13:44------PURPORT).

Kṛṣṇa was playing like a dramatic actor. Because Brahmā had some false prestige, thinking that he had some power, Kṛṣṇa showed him his real position. A similar incident occurred when Brahmā went to see Kṛṣṇa in Dvārakā. When Kṛṣṇa's doorman informed Lord Kṛṣṇa that Lord Brahmā had arrived, Kṛṣṇa responded, "Which Brahmā? Ask him which Brahmā." The doorman relayed this question, and Brahmā was astonished. "Is there another Brahmā besides me?" he thought. When the doorman informed Lord Kṛṣṇa, "It is four-headedBrahmā," Lord Kṛṣṇa said, "Oh, four-headed. Call others. Show him." This is Kṛṣṇa's position. For Kṛṣṇa the four-headed Brahmā is insignificant, to say nothing of "four-headed scientists." Materialistic scientists think that although this planet earth is full of opulence, all others are vacant. Because they simply speculate, this is their scientific conclusion. But from the Bhāgavatam we understand that the entire universe is full of living entities everywhere. Thus it is the folly of the scientists that although they do not know anything, they mislead people by presenting themselves as scientists, philosophers and men of knowledge.

(SRIMAD BHAGAVATAM------10:13:61------PURPORT).

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