Mahabharata 4.10.12

4.10.12

sa śikṣayāmāsa ca gītavāditaṃ sutāṃ virāṭasya dhanaṃjayaḥ prabhuḥ |
sakhīśca tasyāḥ paricārikāstathā priyaśca tāsāṃ sa babhūva pāṇḍavaḥ || 12 ||

"Vaisampayana continued, 'The king of the Matsyas then tested Vrihannala in dancing, music, and other fine arts, and consulting with his various ministers forthwith caused him to be examined by women. And learning that this impotency was of a permanent nature, he sent him to the maiden's apartments. And there the mighty Arjuna began giving lessons in singing and instrumental music to the daughter of Virata, her friends, and her waiting-maids, and soon won their good graces. And in this manner the self-possessed Arjuna lived there in disguise, partaking of pleasures in their company, and unknown to the people within or without the palace.'"