There has been much controversy about whether divorced and remarried persons should be permitted to receive Communion. By divorced and remarried, we mean:
1. a person who has a previous marriage,
2. to a person still living,
3. which seem to have the conditions for validity,
4. yet the person is divorced, and
5. he or she has entered into a second marriage-like relationship,
6. which includes sexual intercourse,
7. yet which lacks the conditions for validity.
The Church permits repentant persons who are divorced and remarried to sometimes remain with their second invalid “spouse” for the sake of the children, while practicing perfect and perpetual abstinence. So the determination that the person actually meets all these conditions is usually made in Confession or in a private and frank conversation with the local pastor. Other persons, especially those outside the parish or diocese, who have no knowledge of the persons and relationship in question, should not assume the couple is sexually active.
Supposing a divorced and remarried person as described above (with all 7 conditions), Pope Francis in Amoris Laetitia has permitted the possibility of Communion, after consultation with the pastor and possibly Confession. This permission is based on the possibility that such a person might still be in the state of grace, despite objective mortal sins, because their acts either lack the full culpability of actual mortal sin, or they are repentant (but often fall back into the same sin).
From this discussion, a related question arises. Will the divorced and remarried go to Heaven, if they are having sexual relations in their second relationship, despite a valid first marriage? Such sexual acts are adultery, and the fact that the second relationship is approved by the secular government as a civil marriage does not make the sexual acts moral.
The answer is fairly simple. If the person in question has no other unrepentant actual mortal sin, and they are a baptized Christian, they would be in the state of grace if the acts of adultery (due to divorce and remarriage) are not committed with full knowledge and full deliberation (or if they repent, of course).
Neither is it correct to say that if they simply know what the Church teaches, they have full knowledge. Rather, the person would need to have more than the mere reception of information to meet that condition for an actual mortal sin. An atheist may well know what the Church teaches, but he does not accept the teaching as truth. He does not subjectively appropriate those truths to his own conscience, such that he would sin against conscience and against God by contradicting that knowledge. And the same is true, to some extent, for Catholics, especially those who are poorly-catechized, who have not had the benefits of being raised in a practicing Catholic family, etc.
We cannot assume that all or most of the divorced and remarried Catholics have full knowledge. Similarly, full deliberation is not merely a length of time, but also the fullness of the freedom with which the person exercises their will. And this may be reduced by difficult circumstances, such as a civil spouse who would cause grave harm to the partner or children.
But certainly if a person commits adultery in any circumstance, for any motive, with the conditions met for an actual mortal sin, they will not be saved unless they repent. One unrepentant actual mortal sin condemns to Hell forever, and there are in fact many human souls in Hell now, and many more will be added as times passes (unfortunately).
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