Is celebrating Christmas Blasphemy?
noun: blasphemy; plural noun: blasphemies
The action or offence of speaking sacrilegiously about God or sacred things; profane talk.
"he was detained on charges of blasphemy"
Synonyms: profanity, profaneness, sacrilege, irreligiousness, irreverence, taking the Lord's name in vain, swearing, curse, cursing, impiety, impiousness, ungodliness, unholiness, desecration, disrespect; formalimprecation; archaicexecration
"he was condemned for his blasphemy"