Sokar was an ancient falcon god in the environs of Memphis who perhaps was originally associated with craftsmanship. However, he came to be a god of the necropolis of that area and rose, in time, to considerable importance as a chthonic and afterlife deity. The Pyramid Texts frequently mention the god in an afterlife context where the deceased king is said to be raised into the "henu barque" of Sokar and equated with Osiris, but only after the rise of Osiris to importance. The Pyramid Texts describe Sokar as a god active in the rebirth of the king and in the ceremonies of confirmation and transfer of royal power. 

However, Sokar was associated with the Memphite god Ptah as the synchronistic Ptah-Sokar even before Sokar's association with Osiris. This was perhaps an easy link because Ptah too was a god of craftsmanship. In fact, Sokar took Ptah's consort, Sekhmet as his own. In this form, Ptah-Sokar associates the wealth of the soil and its power of growth. 

By the Middle Kingdom, all three of the gods were combined into the tripartite deity, Ptah-Sokar-Osiris, who remained an important funerary deity for most of the remainder of Egypt's dynastic history. Then, he assumes a specific role in the transfiguration at death and in the Opening of the Mouth ceremony.

During the New Kingdom Period, the Book of the Dead presents Sokar as an image of the world unified in Osiris. The terrestrial Ptah-Sokar became Sokar-Osiris, the nocturnal incarnation of the sun during the fourth and fifth hours of the Amduat. He allowed the sun to complete its course during the night and to be reborn in the morning. It should be noted that during the New Kingdom, the priests of Sokar have the same titles as the Memphite clergy of Ptah did in the Old Kingdom, but now they almost always refer to the high priests of Heliopolis. 

Sokar is also related to two groups of deities, including the Memphite group which included Khnum and a solar group that consisted of Nefertem and the five divine daughters of Re. The "Memphite Khnum is among the deities listed in the Sokar chapel and the hall of Sokar and Nefertem in the temple of Seti I at Abydos. Nephthys could also be his companion. Called "father and mother", Sokar really has no family as such, though Redoudja is identified as "son of Sokar" in Spell 941 of the Coffin Text.

Sokar had a number of epithets, such as "he of Rosetau", which refers to a site near the Sphinx of Giza, though ultimately indicated any necropolis. This also came to represent the mouth of the passages into the Underworld. He is also the "lord of the mysterious region", also referring to the underworld. Another is the "great god with his two wings opened, which emphasizes his unrestricted movement and power in the afterlife.  

Sokar could be ichnographically depicted in various ways in addition to that of the falcon which appears to have been his original form. The falcon which seems ever present in his representations evokes his divine ability to fly through the underworld, on earth and in the heavens. In the more symbolic forms he is shown as a falcon's head, which is sometimes set in a boat, surmounting an earthen funerary mound. In this regard, an image depicted in vignettes of the Amduat refers to him as "he who is upon his sand". 

As a falcon-headed man, Sokar is often depicted as mummiform and sometimes is adorned with a complicated conical crown that includes disk horns and cobras, not unlike that of the atef-crown. Sometimes he wears the White Crown and holds a scepter and a whip, the regalia of Osiris. As a falcon, he can also be related to Horus, and like him, may sometimes where the Double Crown. Specifically, in the tomb of Tuthmosis III on the West Bank at Thebes (modern Luxor) in the Valley of the Kings, he is shown as a falcon headed god standing on a multi-headed chthonic serpent, emphasizing his power over the nether regions and their inhabitants. One of the most impressive surviving examples of his falcon headed iconography is found in the shape of the silver coffin of Sheshonq I which was found at Tanis. 

During the later periods, his mot common representation is in the form of Ptah-Sokar-Osiris. From the Late Period onwards, small statuettes of the combined deity were made that depict him as a mummiform human-headed god standing upright on a sarcophagus-like box or pedestal, frequently surmounted by Sokar's falcon head image. The base sometimes contained a Book of the Dead.  Ptah-Sokar-Osiris could also be depicted as a squat, pygmy-like male, sometimes with a scarab beetle on his head. The amuletic deity Pataikos seems to have been derived from these particular Ptah-Sokar-Osiris figures. During the Greek Period, the Osirian form of Sokar reached its zenith.

The emblems of Sokar include his henu (hnw) barque, onions and geese. His barque represents solar triumphs and is set on a sledge. At its prow may be the head of an antelope or a bull. Along the edge of the hull of the barque may be int-fish and birds (falcons or swallows. In the center of the barque is a mound shaped chapel surmounted by his falcon head. At the stern are three or four rudder pins. 

Even though there has not been any archaeological evidence of a temple solely dedicated to Sokar, Memphis remained the primary cult center of god and it was there, at least by the early Old Kingdom, that the great Sokar (or Choiak) took place each year during the fourth month of the spring akhet season. At this time, the god was carried from his temple to assist the king in ceremonial activities including the hoeing of the earth or the digging of ditches or canals. During the Middle Kingdom, the festival incorporated Osirian aspects of festivals in Abydos. During the New Kingdom and alter times, the festival was also celebrated with great ado in western Thebes, where it is depicted in reliefs in the Temple of Ramesses III at Medinet Habu, and where it rivaled the great Opet Festival. This festival appears to have stressed the continuity of the royal mortuary cult along with the resurrection of Sokar and. During the ceremony, the image of the god was probably carried in his distinctive henu barque, which had a cabin that symbolized a funerary chest surmounted by a falcon. 

He was venerated in a number of other areas of Egypt. He became well established in the Fayoum during the Middle Kingdom, and is well represented in the tombs on the West Bank at Thebes. During the New Kingdom, he is also represented at Karnak, and can be found in the chapel cavern of Anubis on the second terrace of Hatshepsut's temple, as well as in the Tuthmosis I chapel on the third terrace at Deir el-Bahri. Tuthmosis III dedicated a suite of rooms to Sokar in Akh-menu and Amenhotep III consecrated a monumental architectural ensemble in his temple of "millions of years" at on the West Bank at Thebes. 

During the Ramessid period, he is found at Gurneh in Hall IX of the temple of Seti I, and was also given a cult site in the temple constructed by Seti I at Abydos. Furthermore, Ramesses II provided a group of rooms in the Ramesseum consecrated to Sokar, and he also had the deity depicted on the peripheral wall of the temples of Amun-Re at Karnak.  During the Greek (Ptolemaic) Period, a chapel was dedicated to him in the temple of Horus at Edfu and also in the Hathor temple at Dendera. The last known representation of Osiris-Sokar with a falcon's head was done under Emperor Caracalla at Philae. 

Beyond funerary beliefs, the veneration of Sokar is difficult to ascertain. Amulets of Sokar are not common, but some depicting a squatting, mummiform falcon may represent the god. 

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