Shiva Purana
तस्मिन्नवसरे साक्षाद्भगवानिन्दुभूषणः ॥ शक्तिं तयोरपि द्रष्टुमरूपो रूपमास्थितः ॥ ४४ ॥
On that occasion the Supreme Personality of Godhead, who adorns the moon, appeared personally. The formless assumed form to see the power of both of them.
english translation
tasminnavasare sAkSAdbhagavAnindubhUSaNaH ॥ zaktiM tayorapi draSTumarUpo rUpamAsthitaH ॥ 44 ॥
hk transliteration by Sanscript