Did Laodicea Actually Prohibit Accepting Unleavened Bread from Yahudim?

Council: Laodicea (4th c.) · Evidence: Canon 38

What the ancient record says

Yes. Canon 38 prohibits receiving unleavened bread from Yahudim.

Greek: ἄζυμα (azyma). Not a vague ban on "foreign food", it specifically addresses unleavened bread associated with Yahudi observance, deeply connected with Pasakh and the appointed time of Unleavened Bread, reaching one of the most recognizable practices of the ancestral calendar.

The canonical tradition connects accepting the unleavened bread with participation in what the council condemns as the other community's religious practice; the language is openly negative (show it, don't sanitize). A prohibition against accepting it strongly indicates the practice/temptation existed (how common, unknown).

Three canons together, 29: do not rest on Shabbath / work on it; 37: no Yahudi festival gifts or celebrating with them; 38: no unleavened bread, a boundary-building pattern, hard to dismiss as one isolated regulation. Not all invented by Constantine, separation had been developing; the 4th century increasingly turns developing boundaries into formal institutional rules (the documentable development).