Why did Julian’s policies upset many Christians in Antioch?

In Antioch, Julian’s policies deeply offended the Christian population primarily through his efforts to suppress their religious influence and promote paganism.

Specifically, his actions in the city included:

• Closure of the Basilica: Julian ordered the closing of the city's great Christian basilica.1
• Removal of Relics: He oversaw the removal of the relics of the martyr Babylas from the sacred grove of Daphne, an act that was viewed as a direct affront to the Christian community.1

These measures were part of a broader campaign during his reign to restore paganism as the official religion of the empire. Beyond these specific actions in Antioch, Christians were further alienated by his broader policies, such as prohibiting them from teaching classical literature and philosophy, as well as his public ridicule of their faith in his writings. His personal austerity and his pamphlet Misopogon ("Beard Hater"), in which he criticized the citizens of Antioch for mocking his appearance and religious devotion, further exacerbated tensions between the emperor and the city's inhabitants.12