"If, therefore, the Catholic Church also claims the right of dogmatic
intolerance with regard to her teachings, it is unjust to reproach her
for exercising this right...She regards dogmatic intolerance not alone
as her contestable right, but also as a sacred duty...According to
Romans 8:11, the secular authorities have the right to punish, especially
grave crimes with death; consequently, 'heretics may be not only
excommunicated, but also justly put to death.'"
[The Catholic Encyclopedia, 1911 Edition, Vol. 14, pp.776,768]