After his father, Antiochus IV is perhaps the best known of the Seleucid kings. He appears most often in the western tradition as the villain in the Maccabean struggle. Antiochus’ repression of the Jewish revolt and the transformation of the temple of Jerusalem to one of Zeus presented through the Jewish tradition painted him as a religious fanatic. To some extent this portrayal was present in other contemporary sources, Polybius recounts the story of how he was called Epimanes (mad) instead of Epiphanes (illustrious) by the citizens of Antioch:
Antiochus Epiphanes, nicknamed from his actions Epimanes, would sometimes steal from the royal palace leaving his attendants behind, and appear wandering about any part of town with two or three companions . .. Often he would take off his royal dress, put on a tebenna and go about the agora canvassing for office, shaking hands with some and embracing others and urging them to vote for him, sometimes as aedile (agoranomos) sometimes as tribune (demarchos). And when he got the office and sat on the ivory chair in accordance with the Roman custom, he would listen to the suits which took place in the agora and would give his verdict with great seriousness and attention.
Polybius XXVI.1
Another important aspect in modern analysis of Antiochus' motives in Jerusalem was his general devotion to the gods, and Zeus in particular (leaving aside the question of his assimilation to Zeus). To some extent his dedications can be seen as part of normal Hellenistic euergetism.
However, his piety was also noted by some ancient authors:
As to his generosity towards the gods, the temple of Olympian Zeus at Athens can bear witness, the only temple in the world undertaken on a scale commensurate with the greatness of the god. But he also embellished Delos with magnificent altars and numerous statues, while at Antioch he promised to build among many other buildings in various places a magnificent temple of Jupiter Capitolinus . . . He also surpassed all previous kings in the magnificence of the shows of every kind he offered. Most of them conformed to his usual style and were staged by a large number of Greek artists, but he also put on gladiatorial games in the Roman style. At first this caused more alarm than pleasure to men who were not used to such a spectacle, but later by multiplying the shows and allowing the fighters to go only as far as wounds while sometimes even having fights without quarter, he familiarized men with this spectacle and made it popular, and filled most young men with an enthusiasm for arms.
Livy XLI.20
The modern perception of Antiochus IV's religious interactions with Jerusalem have undergone a major shift in part owing to the recognition of the problems with the sources.