As adjectives the difference between unchristian and unchristianly
is that unchristian
is not of the christian faith while unchristianly
As an adverb unchristianly is
in an unchristian way.
Other Comparisons: What's the difference?
Not of the Christian faith.
Not in accord with Christian principles; without Christian spirit, unbefitting a Christian.
*2009 , (Diarmaid MacCulloch), A History of Christianity , Penguin 2010, p. 215:
*:Arius [...] eventually died obscurely, reputedly as the result of an acute attack of dysentery in a latrine in Constantinople, which circumstance afforded his enemies some unchristian pleasure, and was eventually commemorated with exemplary lack of charity in the Orthodox liturgy.