The Unity of the Church (Excerpt):

For, dear brethren, there has now appeared a new source of disaster and as if the fierce storm of persecution had not been enough, there has come to crown it a subtle evil, an innocent-seeming pestilence, which masquerades as compassion. Contrary to the law of Our Lord and God, through certain people’s presumption a deceptive readmission to Communion is being granted, a reconciliation that is null and void, one that imperils the givers and is worthless to those who receive it. The latter no longer seek the slow painful road to recovery, not the genuine cure through satisfaction done… The wounds they are dying of are covered up and, through pretense of lack of pain, the mortal affliction deep in their organism is concealed. People coming back from the altars of Satan approach Our Lord’s sacred body, their hands still foul and reeking.

St. Cyprian of Carthage, The Lapsed, The Unity of the Church, Paulist Press, pp.24-25