Why is Sāvan (Śrāvaṇa) Śiva’s month, and when does it start?

tradition links it to Śiva drinking the poison from the churning of the ocean; it starts about two weeks earlier in Pūrṇimānta (North) than in Amānta regions.

The best-known story is that during the churning of the ocean, the poison hālāhala rose first, and Śiva held it in his throat to save the world, becoming Nīlakaṇṭha. The devas poured water on him to cool him, and so devotees offer jala-abhiṣeka through this monsoon month. The rains also make it a natural time for inward practice.

What people do: Sāvan Somvār fasts, daily water or milk on the liṅga, bel-patra, Rudrābhiṣeka, the Kāṁvar Yātrā carrying Gaṅgā water, and Mangalā Gaurī vrat on Tuesdays for women.

Dates: in the North (Pūrṇimānta), Sāvan begins the day after Āṣāḍha Pūrṇimā. In Maharashtra, Gujarat, Karnataka and the Telugu states (Amānta), Śrāvaṇa begins after Āṣāḍha Amāvasyā, about fifteen days later. So Sāvan Mondays differ by region; follow your local panchang.

Story: Śiva as Nīlakaṇṭha (samudra-manthana) · Source: Bhāgavata and Śiva Purāṇa tradition

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