The Discourse about Mucalinda
Thus I heard: At one time the Gracious One was dwelling near Uruvelā, on the bank of the river Nerañjarā, at the root of the Mucalinda tree, in the first period after attaining Awakening. Then at that time the Gracious One was sitting in one cross-legged posture for seven days experiencing the happiness of freedom.
Then at that time a great cloud arose out of season, bringing seven days of rainy weather, cold winds, and overcast days. Then the Nāga King Mucalinda, after leaving his domicile, and surrounding the Gracious One’s body seven times with his coils, stood with his great hood stretched out above his head, thinking:
Then with the passing of those seven days, the Gracious One arose from that concentration. Then the Nāga King Mucalinda, having understood that the sky was now clear without a cloud, having unravelled his coils from the Gracious One’s body, and after withdrawing his own form, and creating the appearance of a young brāhmaṇa, stood in front of the Gracious One, revering the Gracious One with raised hands.