Lactantius was a Christian writer in the 3rd and 4th century who wrote the Divine Institutes to explain Christianity to Roman critics, to whom it must have seemed quite foreign. Apparently, his wise words were often ignored through the centuries.
Religion is to be defended, not by putting to death, but by dying; not by cruelty, but by patient endurance; not by guilt, but by good faith: for the former belong to evils, but the latter to goods; and it is necessary for that which is good to have place in religion, and not that which is evil. For if you wish to defend religion by bloodshed, and by tortures, and by guilt, it will no longer be defended, but will be polluted and profaned.
Lactantius, Divine Institutes, book 5, chapter 20, from the 10 volume 1885 translation in The Ante-Nicene Fathers
A translation of the Divine Institutes can be found online from several sources.