Greek religion was not based on a written creed or body of dogma. Nevertheless, certain sacred writings survive in the form of hymns, oracles, inscriptions, and instructions to the dead. Most elaborate are the Homeric Hymns, some of which may have been composed for religious festivals, though their subject matter is almost entirely mythological. Delphic inscriptions include hymns to Apollo but, like the Epidaurian hymn by Isyllus to Asclepius, they are not concerned with liturgy. Delphic oracles are quoted from literary sources but appear, on the whole, to be retrospective concoctions, like the Hebraic-Hellenistic collection of Sibylline prophecies. Questions scratched on folded lead tablets have been found at Dodona, and detailed instructions to the dead, inscribed on gold leaf and possibly of Orphic inspiration, have been found in Greek graves in southern Italy. Papyrus fragments of similar character have been recovered from graves in Macedonia and Thessaly.

Shrines and temples

In the earliest times deities were worshipped in awesome places such as groves, caves, or mountaintops. Mycenaean deities shared the king’s palace. Fundamental was the precinct (temenos) allotted to the deity, containing the altar, temple (if any), and other sacral or natural features, such as the sacred olive in the temenos of Pandrosos on the Athenian Acropolis. Naoi (temples—literally “dwellings”—that housed the god’s image) were already known in Homeric times and, like models discovered at Perachora, were wooden and of simple design. Poros and marble replaced wood by the end of the 7th century bc, when temples became large and were constructed with rows of columns on all sides. The image, crude and wooden at first, was placed in the central chamber (cella), which was open at the eastern end. No ritual was associated with the image itself, though it was sometimes paraded. Hero shrines were far less elaborate and had pits for offerings. Miniature shrines also were known.

Most oracular shrines included a subterranean chamber, but no trace of such has been found at Delphi, though the Pythia was always said to “descend.” At the oracle of Trophonius, discovered in 1967 at Levádhia, incubation (ritual sleep to induce a dream) was practiced in a hole. The most famous centre of incubation was that of Asclepius at Epidaurus. His temple was furnished with a hall where the sick were advised by the demigod in dreams. Divination was also widely practiced in Greece. Augurs interpreted the flight of birds, while dreams and even sneezes were regarded as ominous. Seers also divined from the shape of altar smoke and the conformation of sacrificial animals’ entrails.

Priesthood

Even in the state cults, priesthoods were frequently ancestral prerogatives. Eteobutads organized the cult of the hero-king Erechtheus at Athens; Praxiergids superintended the washing of Athena’s robes at the Plynteria; and Clytiads and Iamids officiated at the altar of Zeus at Olympia. Although there was no official clergy, since the religious and secular spheres were not sharply divided, professional assistance was available at sacrifices. There was no necessary correspondence between the sex of deities and that of priests. Hera and Athena favoured priestesses, but Isis and Cybele favoured priests. Apollo inspired the Pythia (priestess) at Delphi but a priest at Ptoon. The mysteries at Eleusis were administered by the Eumolpids and Kerykes. The latter assembled the initiates (mystae), while the former provided the Hierophant, who revealed the mysteries in the torch-lit Anaktoron (king’s shrine) within the great Telesterion, or entrance hall.

Festivals

The precise details of many festivals are obscure. Among the more elaborate was the Panathenaea, which was celebrated at high summer; every fourth year it was celebrated on a more splendid scale (the Great Panathenaea). Its purpose, besides offering sacrifice, was to provide the ancient wooden image of Athena, housed in the “Old Temple,” with a new robe woven by the wives of Athenian citizens. The Great Panathenaea included a procession, a torch race, athletic contests, mock fights, and bardic recitations. The Great Dionysia was celebrated at Athens in spring. At the end of the ritual the god’s image was escorted to the theatre of Dionysus, where it presided over the dramatic contests. It, like its rural counterpart, included phallic features.

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The Olympic Games formed part of the great festival of Zeus held every fourth summer in the god’s sacred precinct—the Altis beside the river Alpheius in the western Peloponnese. A truce was proclaimed in order to permit any warring Greeks to compete, and the celebrations lasted five days. Sacrifice and libation were made at the altar of Zeus, where omens were taken and oracles proclaimed, and at the tomb of Pelops and the altar of Hestia. Competitors and judges took an oath to observe the rules; processions were held; bards recited; and winners were honoured at state banquets. The richer and more famous were immortalized by lyric poets, such as Simonides, Bacchylides, and Pindar. Though women were banned, girls competed at the festival of Hera. The games held in honour of Zeus at Nemea, Apollo at Delphi, and Poseidon at the Isthmus followed the Olympian pattern.

Rites

Sacrifice was offered to the Olympian deities at dawn at the altar in the temenos, which normally stood east of the temple. Representing as it did a gift to the gods, sacrifice constituted the principal proof of piety. The gods were content with the burnt portion of the offering, while the priests and worshippers shared the remainder of the meat. Different animals were sacred to different deities—e.g., heifers to Athena, cows to Hera, pigs to Demeter, bulls to Zeus and Dionysus, dogs to Hecate, game and heifers to Artemis, horses to Poseidon, and asses to Priapus—though the distinctions were not rigorously observed. The practices of ritual washing before sacrifice, sprinkling barley grains, and making token offerings of hair are described by Homer. Victims were required to be free of blemish, or they were likely to offend the deity. Sacrifice also was made to chthonian powers in the evening. Black-coloured animal victims were offered and placed in pits, and the meat was entirely consumed. Sacrifice preceded battles, treaties, or similar events. Human sacrifice appears, if it was practiced at all, to have been the exception. Bloodless sacrifices were made to some deities and heroes.

Prayers normally began with compliments to the deity, followed by discreet references to the petitioner’s piety, and ended with his special plea. In addressing a prayer to an Olympian, the suppliant stood with his arms raised and palms upward. Processions formed part of most gatherings (panēgyreis) and festivals. The Panathenaic procession set out from the Pompeion (sacred storehouse) at dawn, headed by maiden basket-bearers (kanēphoroi) who carried the sacred panoply. Elders bore boughs (thallophoroi) while youths (ephēboi) conducted the victims for sacrifice, and cavalry brought up the rear. The robe was spread on the mast of a wheeled ship.

The procession to Eleusis to restore the sacred objects, brought by the ephēboi to the Eleusinium sometime previously, followed the wooden image of Iacchus (a personification of the ritual cry), which was escorted by its own priest, the iacchagogos, and officials. The mystae wore myrtle crowns and carried sheaves of grain. Whatever the nature of the mysteries, those initiated returned in a mood of exaltation. Adepts (epoptai) were later admitted to more solemn rites (to see an ear of wheat, scoffers said).