Brown, Peter. “St Augustine’s Attitude to Religious Coercion.” Journal of Roman Studies, Vol. 54 (1964), pp. 107-16.  

Excerpt:

“Augustine had to face the issue of religious coercion throughout his episocpate, and especially in his dealings with the Donatist schism. As far as I know, he is the only writer in the Early Church to discuss the subject at length. He even changed his mind on the issue, and he has told us of this ‘conversion’ with characteristic disarming frankness. It is a change which cannot fail to interest us, for whom the problem remains acutely relevant. He went on to justify religious coercion with a thoroughness and coherence which is quite as much part of his character as is his candour: and so Augustine has appeared to generations of religious liberals as ‘le prince et patriarche des persecuteurs.'”

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