Mbh 1.104.4a

“In this connection there is another old history that I will recite to you. There was in olden days a wise Rishi of the name of Utathya. He had a wife of the name Mamata whom he dearly loved. One day Utathya’s younger brother Vrihaspati, the priest of the celestials, endued with great energy, approached Mamata. The latter, however, told her husband’s younger brother--that foremost of eloquent men--that she had conceived from her connection with his elder brother and that, therefore, he should not then seek for the consummation of his wishes. She continued, ‘O illustrious Vrihaspati, the child that I have conceived hath studied in his mother’s womb the Vedas with the six Angas, Semen tuum frustra perdi non potest. How can then this womb of mine afford room for two children at a time? Therefore, it behoveth thee not to seek for the consummation of thy desire at such a time. Thus addressed by her, Vrihaspati, though possessed of great wisdom, succeeded not in suppressing his desire. Quum auten jam cum illa coiturus esset, the child in the womb then addressed him and said, ‘O father, cease from thy attempt. There is no space here for two. O illustrious one, the room is small. I have occupied it first. Semen tuum perdi non potest. It behoveth thee not to afflict me.’ But Vrihaspati without listening to what that child in the womb said, sought the embraces of Mamata possessing the most beautiful pair of eyes. Ille tamen Muni qui in venture erat punctum temporis quo humor vitalis jam emissum iret providens, viam per quam semen intrare posset pedibus obstruxit. Semen ita exhisum, excidit et in terram projectumest. And the illustrious Vrihaspati, beholding this, became indignant, and reproached Utathya’s child and cursed him, saying, ‘Because thou hast spoken to me in the way thou hast at a time of pleasure that is sought after by all creatures, perpetual darkness shall overtake thee.’