I've been farming Piety (Act 3 Merciless, Lunatic temple version) today, and I noticed she always repeats "Your devotion damns us, heretic!" twice. One time, then another time in a different tone.
I was playing a Templar, and it occurred every time she said that, and in every instance of the fights. Her other dialogs/taunts were not repeated, only this particular phrase.