Srimad Bhagvata Mahapurana: Book 8: Chapter 7: Verses 33-46
The gods and demons proceed to churn the ocean and Lord Siva drinks the poison appearing out of it
They, on the other hand, that revile You as living in the company (excessively fond) of Goddess Uma (Your divine Spouse)-even though Your feet are contemplated upon in the heart by teachers (of mankind) revelling in their Self-and as fierce and violent and particularly fond of the cremation-ground, even though You stand thoroughly disciplined by austerities, have surely not understood Your pastimes and have cast (all) shame to the winds (as otherwise they would not have the impudence to rail at You in this way). (Even) Brahma and others are not capable of correctly comprehending Your essential nature, much less extolling properly You, the perfect One, who are (so mysterious and ) higher (even) than that (Prakrti or primordial Matter) which lies beyond both causes and effects.
How can, therefore, we, who (are very recent in that we) have been created by Marici and others (the creation of Brahma), feel equal to it ? Yet, we have tried to extol You according to our barest capacity. We clearly perceive this (visible form of Yours) alone and not Your transcendent reality, O supreme Lord ! As a matter of fact, Your manifestation is intended (only) to gladden the world, even though Your activities are not (always) open (to the world). (35)Sri Suka went on: Perceiving the aforesaid distress of theirs and sore stricken with mercy, the Lord, who is the Friend of all living beings, told Sati, His beloved Consort, as follows:- Sri Siva observed: Oh, how distressing it is ! Observe, O Bhavani (Consort of Lord Siva, the Source of the universe), this calamity that has come upon these creatures from (the poison called) Kalakuta, produced by the churning of the ocean of milk. Security must be vouchsafed by me to these people, anxious (as they are) to preserve their life. For, to protect the afflicted, this much is the concern (duty) of a great one (who is endowed with power). The virtuous protect (other) living beings by (sacrificing) their own transient life. Sri Hari, the Soul of the universe, 0 good lady, is pleased with a man who shows mercy to created beings that are bewildered by the deluding potency of the Supreme Spirit and have contracted enmity with one another. (And) when Lord Sri Hari is pleased, I (too) feel gratified along with the (whole) mobile (animate) and immobile (inanimate) creation. Therefore, I (hereby) swallow this poison. May a happy (prosperous)life be assured to (all) created beings through Me.
Sri Suka continued: Having thus sought leave of Bhavani, Lord Siva (the Delighter of the universe) proceeded to swallow that poison. And Sati, who was aware of His greatness, heartily gave Her consent. Then, squeezing into (the cavity of) His palm the Halahala, which was spreading all round, Lord Siva (the supreme Deity), the Protector of (all) living beings,swallowed it out of compassion. The poison (which was the concentrated impurity of the oceanic water) showed its power even on His person in that it made Him (look) blue at the throat, although the spot became a special ornament to that benevolent Soul. Generally noble souls are afflicted at the agony of the world. For, that (viz., sharing the affliction of others) constitutes the highest worship of the supreme Person, the Soul of the universe. Observing that (benevolent) act of Lord Siva (the Source of blessedness), the god of gods, who showers blessings on His devotees, the created beings (who had approached Him), as well as Sati (Daksa's Daughter), Brahma and Lord Visnu (too) applauded it. Scorpions, snakes and poisonous herbs as well as what other biting creatures (dogs, jackals and so on) there were took in what little (of the poison) leaked from the palm of Lord Siva (even) while He drank it.
SThus ends the seventh discourse, forming part of the story of the churning of the ocean for (obtaining) nectar, in Book Eight of the great and glorious Bhagavata-Purana, otherwise known as the Paramahamsa-Samhita.