Srimad Bhagvata Mahapurana: Book 10: Chapter 2: Verses 1-16
The Lord enters the womb of Devaki and is extolled by the gods
Sri Suka resumed : Conjoined with Pralamba, Baka, Canura, Trnavarta and Aghasura (who in the form of a python ate much), Mustika, Arista, Dwivida, Putana, Kesi and Dhenuka, as well as with other demon kings, the foremost of whom were Bana and Bhauma, and with Jarasandha (the ruler of Magadha, whose two daughters had been married to him) as his ally, the powerful Kamsa set about (the task of) destroying the Yadus. Hard pressed, they migrated to the territories of the Kurus, Pancalas and Kekayas, Salvas, Vidarbhas, Nisadhas, Videhas and Kosalas too. Remaining faithful to him, a few kinsmen (of theirs, however,) continued to serve him. When six boys of Devaki had been killed by Kansa (the son of Ugrasena), a ray of Lord Visnu, whom the devotees speak of as Lord Ananta, entered the womb of Devaki as her seventh child, that went to enhance her delight and grief at the same time. Perceiving the fear born of Kamsa to the Yadus, His proteges, the Lord too, the Soul of the universe, commanded (as follows) Yogamaya (His transcendent creative energy):-- "Proceed, 0 good goddess, to Vraja enriched by cowherds and cows.
Rohini, Vasudeva's wife, is staying in the village of Gokula owned by Nanda; and, afraid of Kamsa, his other wives too are residing in secret places. There exists in Devaki's womb, in the form of an embryo, My own part manifestation known by the name of Sesa (the serpent-god). Taking it out, place it in the womb of Rohini. Then I shall assume the role of a son of Devaki with all My divine potencies, which constitute so many parts of My being as it were, 0 blessed lady; while you shall be born of Yasoda, the wife of Nanda. People will worship you by means of incense, offerings of food and other presents, recognizing you as the supreme controller (of the destinies) of men seeking various boons and as the bestower of all desired blessings.
Men will erect temples (sacred to you) on earth and give (diverse) appellations (to you) such as Durga, Bhadrakali, Vijaya, Vaisnavi, Kumuda, Candika, Krsna, Madhavi and Kanyaka, Maya, Narayani, Irani, Sarada and Ambika. People on earth will call the son of Rohini Sankarsana, particularly because of his being taken out of the womb (of Devaki); by the name of Rama because of his giving delight to the world and Bala because of his pre-eminence among those possessed of strength. " Thus instructed by the Lord and accepting His command with the words, "0 yes, let it be so !" and going round Him from left to right (as a mark of respect), the goddess descended on earth and carried out His behest as she was told. When the embryo in the womb of Devaki was transferred to that of Rohini by Yogamaya (who represents the Lord's trance-sleep at the time of universal dissolution), the people of Mathura wailed aloud saying, "Ah! the embryo (in the womb of Devaki) has perished !" The Lord too, who is the Soul of the universe and rids His devotees of (all) fear, entered the mind of Vasudeva with all His divine potencies constituting parts of His being as it were.