Osiris, also called Usir, one of the most important gods of ancient Egypt. The origin of Osiris is obscure; he was a local god of Busiris, in Lower Egypt, and may have been a personification of chthonic (underworld) fertility. By about 2400 bce, however, Osiris clearly played a double role: he was both a god of fertility and the embodiment of the dead and resurrected king. This dual role was in turn combined with the Egyptian concept of divine kingship: the king at death became Osiris, god of the underworld; and the dead king’s son, the living king, was identified with Horus, a god of the sky. Osiris and Horus were thus father and son. The goddess Isis was the mother of the king and was thus the mother of Horus and consort of Osiris. The god Seth was considered the murderer of Osiris and adversary of Horus. According to the form of the myth reported by the Greek author Plutarch, Osiris was slain or drowned by Seth, who tore the corpse into 14 pieces and flung them over Egypt. Eventually, Isis and her sister Nephthys found and buried all the pieces, except the phallus, thereby giving new life to Osiris, who thenceforth remained in the underworld as ruler and judge. His son Horus successfully fought against Seth, avenging Osiris and becoming the new king of Egypt. Osiris was not only ruler of the dead but also the power that granted all life from the underworld, from sprouting vegetation to the annual flood of the Nile River. From about 2000 bce onward it was believed that every man, not just the deceased kings, became associated with Osiris at death. This identification with Osiris, however, did not imply resurrection, for even Osiris did not rise from the dead. Instead, it signified the renewal of life both in the next world and through one’s descendants on Earth. In this universalized form Osiris’cult spread throughout Egypt, often joining with the cults of local fertility and underworld deities.
Isis was the Egyptian goddess of Magic and Life - the patron saint of mothers, women, and children. She was also known as the goddess of healing. Her name literally means 'Queen of the Throne', which was portrayed by the throne emblem on her head. The hieroglyph of her name meant 'she of flesh' (or mortal) originally, and she may have represented historical queens and female deities. Ancient Egyptians believed that Isis's tears of sorrow for her dead husband Osiris caused the Nile River to flood every year. Isis's origin is uncertain, but she is believed to have come from the Nile Delta. Unlike other Egyptian deities, she didn't have a centralized cult at any time throughout her worship. The first historical mentions of Isis are found as far back as the Fifth dynasty of Egypt, when the first literary inscriptions are found. Her cult became prominent later in Egyptian history, and it absorbed the cults of many other goddesses.
Horus was known as God of the Sky and Sun in Ancient Egypt, and refers to two separate deities of Ancient Egyptian Religion: Horus the Elder (Heru-ur) and Horus the Younger (Heru-pa-khart), as well as a number of minor deities. The original form of Horus is thought to be God of the Sky - his name meaning 'high' or 'distant'. He was seen as a great falcon with large outstretched wings, whose right eye was the sun and left eye was the moon. Since the Falcon God Horus was said to be the sky, he was considered to also contain the Sun and Moon. They traversed the Egyptian sky when Horus, as a falcon, flew across it. Horus became known as Harmerty - 'Horus of two eyes'. The Ancient Egyptian explanation for the sun shining brighter than the moon was explained by a tale known as the contestings of Horus and Set, which was a metaphor for the conquest of Lower Egypt by Upper Egypt around 3000 B.C. It was said that Set, the patron of Upper Egypt, and Horus, the patron of Lower Egypt, engaged in a battle for control of Egypt. Neither side was victorious, until eventually the deities sided with Horus.