Tiberius had been to Rhodes, to a soothsayer of renown, to instruct himself in the rules of astrology. He had attached to his person the celebrated astrologer Thrasyllus, whose fate-revealing science he proved by one of those pleasantries which are only possible with tyrants.
Whenever Tiberius consulted an astrologer he placed him in the highest part of his palace, and employed for his purpose an ignorant and powerful freedman, who brought by difficult paths, bounded by precipices, the astrologer whose science his Majesty wished to prove. On the return journey, if the astrologer was suspected of indiscretion or treachery, the freedman threw him into the sea, to bury the secret. Thrasyllus having been brought by the same route across these precipices, struck Tiberius with awe while he questioned him, by showing him his sovereign power, and easily disclosing the things of the future. Cæsar asked him if he had taken his own horoscope, and with what signs were marked that day and hour for himself. Thrasyllus then examined the position and the distance of the stars; he hesitated at first, then he grew pale; then he looked again, and finally, trembling with astonishment and fear, he cried out that the moment was perilous, and he was very near his last hour. Tiberius then embraced him and congratulated him on having escaped a danger by foreseeing it; and accepting henceforth all his predictions as oracles, he admitted him to the number of his intimate friends.
Tiberius had a great number of people put to death who were accused of having taken their horoscope to know what honours were in store for them, although in secret he took the horoscopes of great people, that he might ascertain that he had no rivalry to fear from them. Septimus Severus was very nearly paying with his head for one of those superstitious curiosities that brought the ambitious of the time to the astrologer. In prosperous times he had gained faith in their predictions, and consulted them about important acts. Having lost his wife, and wishing to contract a second marriage, he took the horoscopes of the well-connected ladies who were at the time open to marriage. None of their fortunes, taken by the rules of astrology, were encouraging. He learnt at last that there was living in Syria a young woman to whom the Chaldæans had predicted that she should be the wife of a king. Severus was as yet but a legate. He hastened to demand her in marriage, and he obtained her; Julia was the name of the woman who was born under so happy a star; but was he the crowned husband which the stars had promised to the young Syrian? This reflection soon began to perplex Severus, and to get out of his perplexity he went to Sicily to consult an astrologer of renown. The matter came to the ears of the Emperor Commodus; and judge of his anger! The anger of Commodus was rage and frenzy; but the event soon gave the response that Severus was seeking in Sicily,—Commodus was strangled.
Divination which had the emperor for its object at last came to be a crime of high treason. The rigorous measures resorted to against the indiscreet curiosity of ambition took more terrible proportions under the Christian emperors.
Under Constantine, a number of persons who had applied to the oracles were punished with cruel tortures.
Under Valens, a certain Palladius was the agent of a terrible persecution. Everyone found himself exposed to being denounced for having relations with soothsayers. Traitors slipped secretly into houses magic formulæ and charms, which then became so many proofs against the inhabitant. The fear was so great in the East, says Ammienus Marcellinus, that a great number burned their books, lest matter should be found in them for an accusation of magic or sorcery.
One day in anger, Vitellius commanded all the astrologers to leave Italy by a certain day. They responded by a poster, which impudently commanded the prince to leave the earth before that date, and at the end of the year Vitellius was put to death; on the other hand, the confidence accorded to astrologers led sometimes to the greatest extremes. For instance, after having consulted Babylus, Nero put to death all those whose prophecies promised the elevation of Heliogabalus. Another instance was that of Marcus Aurelius and his wife Faustina. The latter was struck with the beauty of a gladiator. For a long time she vainly strove in secret with the passion that consumed her, but the passion did nothing but increase. At last Faustina revealed the matter to her husband, and asked him for some remedy that should restore peace to her troubled soul. The philosophy of Marcus Aurelius could not suggest anything. So he decided to consult the Chaldæans, who were adepts at the art of mixing philters and composing draughts. The means prescribed were more simple than might have been expected from their complicated science; it was that the gladiator should be cut in pieces. They added that Faustina should afterwards be anointed with the blood of the victim. The remedy was applied, the innocent athlete was immolated, and the empress afterwards only dreamed of him with great pleasure.
The first Christians were as much addicted to astrology as the other sects. The Councils of Laodicea (366, A.D.), of Arles (314), of Agdus (505), Orleans (511), Auxerre (570), and Narbonne (589), condemned the practice. According to a tradition of the commencement of our era, which appears to have been borrowed from Mazdeism, it was the rebel angels who taught men astrology and the use of charms.
Under Constantius the crime of high treason served as a pretext for persecution. A number of people were accused of it, who simply continued to practise the ancient religion. It was pretended that they had recourse to sorceries against the life of the emperor, in order to bring about his fall. Those who consulted the oracles were menaced with severe penalties and put to death by torture, under the pretence that by dealing with questions of fate they had criminal intentions. Plots without number multiplied the accusations; and the cruelty of the judges aggravated the punishments. The pagans, in their turn had to suffer the martyrdom which they had previously inflicted on the early disciples of Christ—or rather, to be truer, it was authority, always intolerable, whether pagan or Christian, that showed itself inexorable against those who dared to differ from the accepted faith. Libanius and Jamblicus were accused of having attempted to discover the name of the successor to the empire. Jamblicus, being frightened at the prosecution brought against him, poisoned himself. The name only of philosopher was sufficient to found an accusation upon. The philosopher Maximus Diogenes Alypius, and his son Hierocles, were condemned to lose their lives on the most frivolous pretence. An old man was put to death because he was in the habit of driving off the approach of fever by incantations, and a young man who was surprised in the act of putting his hands alternately to a marble and his breast, because he thought that by counting in this way seven times seven, he might cure the stomach-ache, met with the same fate.
Theodosius prohibited every kind of manifestation or usage connected with pagan belief. Whoever should dare to immolate a victim, said his law, or consult the entrails of the animals he had killed, should be regarded as guilty of the crime of high treason.