It was a fact, that the ancient Egyptian corpus of images needed an iconography for expressing the union of Re and Osiris. And little by little in this iconography Isis and Nephthys, the two mourners of Osiris, became essential.
In the XIX Dynasty the ancient Egyptian artists conceived some of the most famous images of this conception combining same as ever iconography.
For instance in the tomb of Nefertari, wife of Ramses II, the chapter 17 of the Book of the Dead was illustrated with the typical image of the corpse with the two mourners Isis and Nephtys, not as women, but as kites.
In this same tomb it was included the Litany of Re; it was an ancient Egyptian religious text, which was inscribed in all Ramesside tombs. It described different forms of the sun god and it stressed specially the symbolic union of Re and Osiris and the identification of the dead king with this dual god.
In this context the ancient Egyptian artist adapted the typical scene mentioned above and represented Isis and Nephthys adoring the image of Re-Osiris, as a hybrid figure with three main features: the body of a mummy evoking Osiris and the ram head with a solar disk recalling Re. The corpse of Re-Osiris could not skip the figures of Isis and Nephthys. As the professional mourners of the mummy, the total resurrection of this god, even being solar and Osirian, depended on them.
But the importance of Isis and Nephthys was so big, that already from the XIX Dynasty they were even included in a pure solar iconography. So, in the lower part of the lintel at the entrance to the tomb of Nefertari the two kites (Isis and Nephthys) were depicted flanking the solar disk.
Under the reign of Sethos I the opening scene of the Litany of Re was for the first time the image of the scarab and the ram-headed god inside the solar disk, which was the depiction of the sun god: young (scarab), plenitude (disk) and maturity (ram-headed god).
At the entrance of the tomb of Merneptah and Siptah the ancient Egyptian artist conceived a new combination of the solar and the Osirian conceptions: the solar disk with the scarab and the ram-headed god flanked by the two goddesses Isis and Nephthys.
So, Isis and Nephthys were crucial for the concept of resurrection. In origin this idea belonged to the Myth of Osiris, but later on it was also transferred to the solar religion. The result was a new iconography from the XIX Dynasty, which became even richer in the XX Dynasty, as we will see in the following post.