ADYTUM is a Greek word, signifying inaccessible, by which is understood the most retired and secret place of the Heathen temples, into which none but the priests were allowed to enter. The adytum of the Greeks and Romans answered to the sanctum sanctorum of the Jews, and was the place from whence oracles were delivered.

ÆRA, a series of years, commencing from a certain point of time called an epocha: thus we say, the Christian æra; that is, the number of years elapsed since the birth of Christ. The generality of authors use the terms æra and epocha in a synonymous sense; that is, for the point of time from which any computation begins.

The ancient Jews made use of several æras in their computation; sometimes they reckoned from the deluge, sometimes from the division of tongues; sometimes from their departure out of Egypt; and at other times from the building of the temple; and sometimes from the restoration after the Babylonish captivity: but their vulgar æra was from the creation of the world, which falls in with the year of the Julian period 953; and consequently they supposed the world created 294 years sooner than according to our computation. But when the Jews became subject to the Syro-Macedonian kings, they were obliged to make use of the æra of the Seleucidæ in all their contracts, which from thence was called the æra of contracts. This æra begins with the year of the world 3692, of the Julian period 4402, and before Christ 312. The æra in general use among the Christians is that from the birth of Jesus Christ, concerning the true time of which chronologers differ; some place it two years, others four, and again others five, before the vulgar æra, which is fixed for the year of the world 4004: but Archbishop Usher, and after him the generality of modern chronologers, place it in the year of the world 4000.

The ancient Heathens used several æras:

1. The æra of the first olympiad is placed in the year of the world 3228, and before the vulgar æra of Jesus Christ 776. 2. The taking of Troy by the Greeks, in the year of the world 2820, and before Jesus Christ 1884. 3. The voyage undertaken for the purpose of bringing away the golden fleece, in the year of the world 2760. 4. The foundation of Rome, in 2856. 5. The æra of Nabonassar, in 3257. 6. The æra of Alexander the Great, or his last victory over Darius, in 3674, and before Jesus Christ 330.

AERIANS, a sect which arose about the middle of the fourth century, being the followers of Aërius, (who must be distinguished from Arius and Aëtius,) a monk and a presbyter of Sebastia, in Pontus. He is charged with being an Arian, or Semi-Arian; but the heaviest accusation against him is an attempt to reform the church; and, by rejecting prayers for the dead, with certain fasts and festivals then superstitiously observed, to reduce Christianity as nearly as possible “to its primitive simplicity; a purpose, indeed, laudable and noble,” says Dr. Mosheim, “when considered in itself: though the principles from whence it springs, and the means by which it is executed, are sometimes, in many respects, worthy of censure, and may have been so in the case of this reformer.” This gentle rebuke probably refers to a report that the zeal of Aërius originated in his being disappointed of the bishopric of Sebastia, (conferred on Eustathius,) which led him to affirm that the Scriptures make no distinction between a presbyter and a bishop, which he founded chiefly on 1 Tim. iv, 14. Hence he is considered by many, as the father of the modern Presbyterians.--“For this opinion, chiefly,” says Dr. Turner, “he is ranked among the heretics, by Epiphanius, his contemporary, who calls it a notion full of folly and madness. His followers were driven from the churches, and out of all the towns and villages, and were obliged to assemble in the woods, caverns, and open defiles.”

AETIANS, another branch (as it is said) of Arians, so called from Aëtius, bishop of Antioch, who is also charged with maintaining “faith without works,” as “sufficient to salvation,” or rather justification; and with maintaining “that sin is not imputed to believers.” It is added, that he taught God had revealed to him things which he had “concealed from the Apostles;” which, perhaps, is only a misrepresentation of what he taught on the doctrine of divine influences.

AFFINITY. There are several degrees of affinity, wherein marriage was prohibited by the law of Moses: thus the son could not marry his mother, nor his father’s wife, Lev. xviii, 7, &c. The brother could not marry his sister, whether she were so by the father only, or only by the mother, and much less if she were his sister both by the same father and mother. The grandfather could not marry his granddaughter, either by his son or daughter. No one could marry the daughter of his father’s wife; nor the sister of his father or mother; nor the uncle, his niece; nor the aunt, her nephew; nor the nephew, the wife of his uncle by the father’s side. The father-in-law could not marry his daughter-in-law; nor the brother the wife of his brother, while living; nor even after the death of his brother, if he left children. If he left no children, the surviving brother was to raise up children to his deceased brother by marrying his widow. It was forbidden to marry the mother and the daughter at one time, or the daughter of the mother’s son, or the daughter of her daughter, or two sisters, together.

It is true the patriarchs, before the law, married their sisters, as Abraham married Sarah, who was his father’s daughter by another mother; and two sisters together, as Jacob married Rachel and Leah; and their own sisters, both by father and mother, as Seth and Cain. But these cases are not to be proposed as examples; because in some they were authorized by necessity; in others, by custom; and the law as yet was not in being. If some other examples may be found, either before or since the law, the Scripture expressly disapproves of them; as Reuben’s incest with Balah, his father’s concubine; and the action of Amnon with his sister Tamar; and that of Herod Antipas, who married Herodias, his sister-in-law, his brother Philip’s wife, while her husband was yet living; and that which St. Paul reproves and punishes among the Corinthians, 1 Cor. v, 1.

AGABUS, a prophet, and as the Greeks say, one of the seventy disciples of our Saviour. He foretold that there would be a great famine over all the earth; which came to pass accordingly, under the emperor Claudius, in the fourth year of his reign, A. D. 44, Acts xi, 28.