Varunapurana 3: vāruṇopapurāṇe tṛtīyo'dhyāyaḥ

The sages said: / Having heard in brief the divine plays of Śambhu that bestow knowledge, / how did that attributeless liṅga, whose nature is Śaṅkara, arise?

Varuṇa said: / The attributeless nature is self-established in him of boundless splendour; / this assumption of form by the Lord is adventitious, O twice-born,

in order to make known his attributelessness and to manifest the nature of the liṅga. / All the deities, O twice-born, are remembered as possessing embodied forms;

the liṅga of Maheśa, however, is attributeless, yet endowed with forms with attributes. / In order to make known the worship of the liṅga, he deluded the two gods.

Deluded at the time of dissolution, the two gods born from the left and right sides of the God of gods / entered into a supreme dispute at that junction:

"I alone am the creator of the world!" "I alone!" said the other. / To awaken the two of them, Hara assumed the form of a liṅga between them,

surrounded by a mass of flames, a mass of splendour, self-luminous. / It arose, and both the husband of Lakṣmī and the creator Brahmā were astonished and deluded.

Beholding this divine splendour, recognizing the Lord as the cause, / and [realizing] the standing of all effects as non-different from the cause,

then Prajāpati and Janārdana swiftly praised [him]. / The gods [said]: / "Obeisance to Rudra, to Soma, to Śaṅka of immaculate form!

Obeisance to Viśaṅka, the most worthy, the tawny one, the ruler! / Obeisance to Bhava, to Śarva, the wielder of the trident, the supreme deity of the liṅga!

Obeisance to the companion of Umā, the divine one, the golden lord! / Obeisance to the three-eyed one! Obeisance to you, the support of the universe!

Obeisance to Mṛḍa, to Nīlakaṇṭha, to the lord of lights! / Obeisance to you, the god with the sky for hair, who wear animal hide!

Obeisance to the overseer of the cave, the secret one, placed within the cave of the heart! / Obeisance to you, the giver of boons, the most worthy, the liṅga of light!"

Praising him thus, the two gods fell to the earth on their knees.
Not seeing the end or the beginning, having assumed the forms of a boar and a bird,

they went, highly astonished, recognizing the God of gods, the Lord. / Saying, "Let us return!" pleased, the sole cause of their pride [removed],

and not seeing the end or the beginning, despondent and bewildered in mind, / they returned there with the gods; approaching Agni, they then said:

The gods [said]: / "Go, O Agni, to the God of gods, the creator who has the form of a liṅga! / What is that incomparable liṅga? What is his power now?

Investigate and tell us, O Fire! Return quickly to us!" / Having heard the gods' words, Agni swiftly went to its vicinity.

Having reached it, seeing the mass of splendour, [asking,] "What deity are you here?"— / as soon as that was uttered by Fire, a voice arose from space:

"What great prowess is in you, O Agni? Reveal that now!" / Having spoken thus, a blade of grass was dropped there; he tried to burn it,

yet Fire, even though terrible, could not [burn it] despite great effort. / Saying, "Obeisance to you, I will go," he ran back to the gods.

The immortals then sent Vāyu with great speed to learn what the God intended; / he too returned, dismissed.

The gods sent the lord of sacrifice, the wielder of the thunderbolt, wishing to see the Lord; / but that splendour vanished.

All the immortals, seeing that auspicious Umā, māyā, / bowed and praised her with devotion, their minds and senses clear.

The gods [said]: / "Obeisance to you, boon-giving goddess, half of Śaṅkara's body! / By you this manifold world shines forth and dissolves, and its maintenance

is obtained here, O Great Goddess, Mahāmāyā, who are the Self of all!" / Then the Goddess laughed and, pleased, spoke to the immortals:

"This is the creator of the world, Hara in the form of the liṅga of light; / he is the leader and beginningless, and the two best gods were deluded,

Brahmā and Viṣṇu, as well as Agni, Vāyu, Indra, and the gods. / Knowledge of his essential nature is exceedingly difficult for you to attain.

Therefore, fashioning an image of the liṅga of the creator who is the form of light, / worship him with devotion in supreme contemplation,

duly with the head-vow and other rites, with [mantras such as] 'Agni is [ash],' / performing the Pāśupata observances, chanting the Śatarudrīya."

With the five-syllable mantra accompanied by the Oṃkāra, O best of gods, / worship Mahādeva, turning away from delusion and indolence.

That pranava, which is the form of brahman, is attributeless and possesses the form of the liṅga; / the liṅga of attributeless Maheśa is said to be attributeless.

Therefore, the liṅga is indeed non-different from brahman in the conception of form, / but for the rest of you, there is only a form with attributes.

Even my own form to be imagined there is spoken of [in that manner], O lordly sages; / with that very non-different form, the gods are established therein.

That very cause has been fashioned for me too, [encompassing] the moving and unmoving; / therefore, worship of the liṅga is meritorious, attributeless, and the cause of knowledge.

Having spoken thus, that lotus-eyed goddess disappeared.
The gods too, having reached their own abode, untiringly [engaged in] worship of the liṅga.

With devotion, they fashioned liṅgas according to their desires; / led by Janārdana, they always worship [them] with devotion.

Whoever tells this meritorious narrative with a wise man / attains the realm of Śiva and gains the knowledge of Śiva.

Thus ends the third chapter, named 'The Explanation of Liṅga Worship', in the Vāruṇa secondary Purāṇa.