So which divine law prevents a heretic from becoming pope?
Divine law is either ius divinum positivum or ius divinum naturale, depending on whether it is revealed or known by reason itself based on the nature of things.
I mean *which* divine law? What is needed is, say for example, against the 1st or 2nd or ? commandment, or reference the pertinent divine revelation from Scripture, this is what is necessary. To say anything is against Divine Law necessarily must at least be able to reference the specific Divine Law itself.
As I explained above: The divine law, which prevents a heretic from becoming pope, is not
ius divinum positivum, so it is
not revealed. Rather, it is
ius divinum naturale, which means that it is
known by reason itself based on the nature of things.
To reference the specific divine law itself, I have quoted and commented on Pope Leo XIII, Pope Pius XII, and St. Robert Bellarmine. Here again the specific divine law (known by reason itself):
By their nature, heresy, schism, and apostasy sever a man from the body of the Church.A man severed from the body of the Church is outside.It is absurd to imagine that he who is outside can command in the Church.The non-Christian cannot in any way be Pope, because he cannot be head of what he is not a member.St. Robert furthermore refers to St. Cyprian, St. Athanasius, St. Augustine, St. Jerome, and others, who explain why a manifest heretic is not a Christian, not a member of the body of Church.
The specific divine law, preventing a heretic from becoming or from remaining Pope, is given
by reason itself based on the nature of things as detailed by Popes, Fathers, and summarized by St. Robert Bellarmine.