Deep in the forest stood the ashram of the mighty sage Gautama and his beautiful wife Ahalya. One day Gautama went, as he always did, to the river, to practice austerities, leaving Ahalaya behind. Indra, the king of the gods, was so enamoured by her beauty that he took the form of her husband and came to the ashram. He said, “I want to make love to you.” Ahalya ecognized Indra beneath the disguise, but she was overcome by desire for the king of the gods and agreed to make love to him. When she was quite satisfied, she sent him on his way.
As luck would have it, Gautama returned to the hermitage just then. Knowing full well what had just happened, he cursed the pair. “You, Indra, king of the gods, you took my form and did what no man must do! May your testicles fall off! And as for you, Ahalya, you will become a frigid stone, breathing and living only on air, rolling in ash and invisible to all! Only when Rama, the son of Dasharatha, comes here, will you be free of this curse!”
Many years later Rama did come and free Ahalya, and as for Indra . . . well, the other gods gave him a pair of ram’s testicles!