Samiddhi Jātaka (No.167)
The Bodhisatta was once a young ascetic in the Himavā, and on one occasion, after wrestling all night with his spirit he bathed at sunrise and stood in one garment to dry his body in the sun. A nymph, seeing him, tried in vain to tempt him.
The story was told in reference to Samiddhi Thera, who had a similar experience on the banks of the Tapodā. Seeing his youth and beauty, a nymph reminded him that he was yet young, asceticism could be practised in old age. Samiddhi replied that no one knew if he would live to see old age. The nymph vanished. J.ii.56‑8.