Can you confess to a person via e-mail?
We will analyze the question that you outlined from the role of the penitent and the confessor.
For the sacrament of reconciliation to be valid, requires, among other things, the declaration of sins by the penitent (this is “confession” as it is properly called, as the act of the penitent ), which must be done verbally, since vocal expression is the most common means for the manifestation of our thoughts.)
Nonetheless, in case of necessity, it would be licit to express sins in writing, by signs or interpretation, but the penitent must always be present to the confessor.
“In what cases can one resort to confession or the declaration of one’s own sins in writing?” Fr. Miguel A. Fuentes indicates that “…one could have recourse to confession in writing to a confessor present in certain cases like the following:
When the penitent is mute or speaks with difficulty;
When the confessor is nearly deaf, or if there is a danger in which others may hear the confessed sins;
For extraordinary shame of the penitent or for the temptation to not mention something;
For lack of memory.
But in these cases, it is convenient that the penitent express vocally to the confessor (if it is possible) that they repent of their sins stated in writing at least by means of some gesture ”, for example, striking their chest, kissing a crucifix, or other similar options.
However, the greatest objection for the validity of a confession via email comes from the part of the confessor given that for the words of absolution are to be valid, they “must be pronounced vocally (even if in a low and imperceptible voice) by the priest over the penitent present at least morally. Vocally, because the words of the priest are the instrument to produce grace in the soul of the penitent. Therefore, a mute priest cannot absolve, and also absolution in writing is invalid (letter, telegram, etc.) ”.
For this reason, the penitent must be present to the confessor, “at least morally”. What does this presence mean? It is not necessary that the penitent be visible to the confessor, for it is sufficient that the priest knows his presence , as occurs applies when one confesses in a confessional with a screen. “In cases of necessity (shipwrecks, earthquakes, war), one can give absolution from any distance (while the penitents are perceived, but sub conditione) ”.
In summary: The true presence of the penitent (at least morally) and the real transmission of the words of absolution conferred by the confessor are required.
Fr. Miguel Ángel Fuentes concludes:
“From what has been said, the probable invalidity of absolution given over telephone, radio or television is inferred since the true presence of the penitent is lacking, and there is no real transmission of the words of absolution, rather, they are electrical vibrations that reproduce the human word. In any case, the Holy See has not proclaimed anything definitively concerning this question. As such, in practice, in cases of extreme necessity (absolute impossibility of being present before a dying person) the priest can and should give absolution sub conditione by telephone or radio; and with much greater reason through a tube or phonetic channel (for example, those used by individuals trapped in a collapsed structure in danger of death)”.
Now in the case of mail, it is clear that one cannot give absolution (in this case it would be “to send the absolution”, because it is not in a vocal medium and we already discussed the invalidity of absolution by writing). Furthermore, Pope Clement VIII condemned and prohibited absolution through a messenger , and here that applies to all kinds of mail, both personal, and electronic. The case of the use of “skype” or communication over a video camera is different, for example, where, in my opinion, it would fall under the same judgement expressed in the preceding paragraph, namely, that it would probably be an invalid absolution, but the priest (given that there exists no definitive pronouncement by the Magisterium on this question) could and should send it “under condition” in cases of extreme necessity.
Fr. Jon M. de Arza, IVE
 Fr. Miguel A. Fuentes says: “Sacramental confession is the voluntary accusation of one’s own sins committed after baptism, made by the penitent to a legitimate priest, in order to obtain absolution from them in virtue of the power of the keys” (FUENTES, M. A., Clothed in Heartfelt Mercy. Manual for the preparation for the ministry of penitence. Editions of the Incarnate Word, San Rafael 52007, 71).
 Idem, 72.
 Idem, 75.
 Cf. Ibidem.
 Idem, 74-75. The underlining is ours.
 Cf. DS 1994/1088.H
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