Matsyapurana 47.182

47.182

buddhvā tadantaraṃ so 'pi daityānāmindranoditaḥ
kāvyasya rūpamāsthāya asurān samupāhvayat //

Unfortunately for the Daityas, Bṛihaspati came to know of the doing of Śukra. He knew for certain that the preceptor of the Daityas would not break his shell of magic for ten years, as he was enjoying himself with Jayantî ; the Devas, on the other hand, also came to know of the weak point of the Daityas, that the latter were ignorant of the distinctive features of their preceptor. They consequently entreated Bṛihaspati to do something for them. Bṛihaspati thus incited by his disciples, personating as Śukra, went and rallied the Daityas round him.—182-183.