Old Egyptian is the earliest attested stage of the Egyptian language, used from roughly the twenty-sixth through twenty-second centuries BCE during the Old Kingdom period, belonging to the Afroasiatic language family's Egyptian branch, a branch entirely distinct from the family's Semitic branch that includes Hebrew, Aramaic and Arabic despite the shared Afroasiatic ancestry many millennia earlier. Old Egyptian is written in hieroglyphic script, a system combining logographic signs representing whole words or concepts with phonetic signs representing sounds, and its most significant religious textual legacy is the Pyramid Texts, a large corpus of funerary spells and rituals carved into the interior walls of royal pyramids beginning with the pyramid of King Unas around the twenty-fourth century BCE, making them among the oldest substantial religious texts to survive from anywhere in the ancient world.
The Pyramid Texts address the deceased pharaoh's journey into the afterlife and his identification with Osiris, god of the dead, and Re, the sun god, establishing theological and ritual patterns that would influence Egyptian funerary religion for the following two thousand years. Old Egyptian religious vocabulary distinguished carefully between several concepts of the human being's spiritual components, including the ka, a kind of vital life force, and the ba, a personality aspect that could travel between the tomb and the world of the living, distinctions the Pyramid Texts assume as established doctrine rather than explain from first principles.