This question doesn’t seem to want to go away and there’s a reason for its persistence: our bishops have not set the example is one reason. The other reason resides in the canon law on the subject. The priest is caught between Scylla and Charybdis.
Only God knows with absolute certainty a person’s state of grace. The individual person can reach a reasonable moral certainty as to the present state of his soul. The priest usually has no knowledge as to a person’s state of grace. Even if a priest knows that a certain person is an habitual sinner, he cannot know if, before coming for Communion, that person has repented, confessed and is striving to remedy his ways.
Even if the priest is practically certain that a person should not receive Communion and would be committing a sacrilege by doing so, he should not publicly refuse to administer the sacrament. No person, not even a grave sinner, should be publicly exposed for hidden faults. Everybody has a right to preserve his good name unless it is lost by the sinner’s public actions or in virtue of a public penalty.
This is a very difficult situation for a priest to be in, but in this way he also shares in that same attitude which the Lord himself adopts in making himself available in the Eucharist. Only rarely will a priest be placed in such a difficult situation; the Eucharistic Lord faces it on a daily basis.
Canon 915 of the Code of Canon Law indicates the principal cases in which Communion may be publicly refused. The canon says, “Those who have been excommunicated or interdicted after the imposition or declaration of the penalty and others obstinately persevering in manifest grave sin are not to be admitted to holy communion.”
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