Owing to this power of awakening life out of death, Osiris became to the Egyptians the special god of the human soul. As lord of the under world, Osiris is often found on the monuments in the shape of a mummy. His colour was in this case black, like his bull in Memphis; his clothing was white;[119] his symbol, a wide-open eye, signifying the second beholding of light. In this form of Osiris the Greeks recognised the Dionysus of their Mysteries, whom they could also compare with Osiris as the giver of fruits.[120] The Egyptians, says Herodotus, were the first to maintain that the soul of man was immortal.[121] Plutarch, as we have already seen, informs us that to the Egyptian Osiris was the embodiment not only of all that is in heaven, but also of all that is in the under world. "His soul," he continues, "was regarded by the Egyptians as eternal and indestructible, and, according to the doctrine of the priests, Osiris ruled over the dead, as Hades and Pluto among the Greeks. In reality, he was free and untouched by everything subject to change and death. When men are delivered from the body, and from pain, and pass into the eternal and invisible world, where pain is unknown, then Osiris becomes their king and leader. They are his retainers, who desire him, and are spectators of a beauty inconceivable and inexpressible to men. This is the explanation of the story most suitable to the deities."[122] The inscriptions on the sarcophagi, the wraps round the corpses, but above all a papyrus roll placed in the coffin with the dead body, the so-called "Book of the Dead," enable us to ascertain with considerable accuracy the views of the Egyptians on the fate of the soul after death. The greater part of the known manuscripts of this book belong to the seventh or sixth century B.C. The contents show that rubrics and prayers of the same purport, but differently drawn up, proceeding from different times, and with different commentaries, are collected together in order to provide the dead person with everything he can want in the next world. All the prayers and invocations for that world are also given, in order that the most effective may be at hand, just as at the end of these manuscripts all the names under which Osiris can be invoked--and they are more than a hundred--are gathered together. But fragments of this Book of the Dead, or, more strictly, this Book of the Resurrection, which forms the core of the Egyptian doctrine of the world to come, are found hewn in sarcophagi--already with a triple commentary--which belong to a date previous to the year 2000 B.C.