Ramayana 1.184b

Then Vishnu, bearing shell, and mace, And discus, showed his radiant face, And thus addressed in smiling glee The Trident wielding deity: "What treasure first the Gods upturn From troubled Ocean, as they churn, Should--for thou art the eldest--be Conferred, O best of Gods, on thee. Then come, and for thy birthright's sake, This venom as thy first fruits take." He spoke, and vanished from their sight, When Siva saw their wild affright, And heard his speech by whom is borne The mighty bow of bending horn,(204) The poisoned flood at once he quaffed As 'twere the Amrit's heavenly draught. Then from the Gods departing went Siva, the Lord pre-eminent. The host of Gods and Asurs still Kept churning with one heart and will. But Mandar's mountain, whirling round, Pierced to the depths below the ground. Then Gods and bards in terror flew To him who mighty Madhu slew. "Help of all beings! more than all, The Gods on thee for aid may call. Ward off, O mighty-armed! our fate, And bear up Mandar's threatening weight." Then Vishnu, as their need was sore, The semblance of a tortoise wore, And in the bed of Ocean lay The mountain on his back to stay. Then he, the soul pervading all, Whose locks in radiant tresses fall, One mighty arm extended still, And grasped the summit of the hill. So ranged among the Immortals, he Joined in the churning of the sea.