The most retired and secret part of the ancient temples, into which the people were not permitted to enter, but which was accessible to the priests only, was called the adytum. Hence the derivation of the word from the Greek privative prefix *a*, meaning “not,” and *dynein*, meaning “to enter”—thus “that which is not to be entered.” In the adytum was generally to be found a tomb or some relics or sacred images of the god to whom the temple was consecrated. It being supposed that temples owed their origin to the superstitious reverence paid by the ancients to their deceased friends, and as most of the gods were men who had been deified on account of their virtues, temples were, perhaps, at first only stately monuments erected in honor of the dead. Thus, the interior of the temple was originally nothing more than a cavity regarded as a place for the reception of a person interred, and in it was to be found the sarcophagus, or coffin, the taphos, or tomb, or, among the Scandinavians, the barrow or mound grave.
In time, the statue or image of a god took the place of the coffin; but the reverence for the spot as one of peculiar sanctity remained, and this interior part of the temple became, among the Greeks, the naos or chapel, among the Romans the adytum, or forbidden place, and among the Jews the kodesh hakodashim, the Holy of Holies (see Holy of Holies).
“The sanctity thus acquired,” says Dudley (*Naology*, page 393), “by the Cell of interment might readily and with propriety be assigned to any fabric capable of containing the body of the departed friend, or the relic, or even the symbol, of the presence or existence of a divine personage.” Thus it has happened that there was in every ancient temple an adytum or most holy place.
The adytum of the small temple of Pompeii is still in excellent preservation. It is carried some steps above the level of the main building and, like the Jewish sanctuary, is without light.