Smalcald Articles- Part III Article IX Of Excommunication

The greater excommunication, as the Pope calls it, we regard only as a civil penalty, and it does not concern us ministers of the Church. But the lesser, that is, the true Christian excommunication, consists in this, that manifest and obstinate sinners are not admitted to the Sacrament and other communion of the Church until they amend their lives and avoid sin. And ministers ought not to mingle secular punishments with this ecclesiastical punishment, or excommunication.

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