Teachings have not changed. Disciplinary practices have.
I trust you recall the “little argument” reported in the Book of Acts where the Church decided in contrast to what had been her practice, that it was no longer necessary to require Gentile men to be circumcised.
That’s an example of disciplinary practice.
Whether or not a man must be circumcised to be baptized is only a matter of discipline? You understand I trust that what is at stake here is not just circumcision but whether Christians were to keep the Law as good Jews? I think the Apostle would be very surprised to hear that this question was simply a matter of disciplinary practice. For Paul the whole truth of the Gospel was at stake here. Consider his letter to the Galatians.
The Church once tolerated slavery. Do we tolerate it anywhere now? But she never taught that slavery was good, and now it is bad.
There are, of course, more slaves in our world than ever before. But I know of no Church that attempts to justify this practice as did the bishops of the Spanish and Portuguese Churches to name only two of the worse offenders. Take a look at a biography of Fr. Bartolome’ de las Casas -
en.wikipedia.org/wiki/Bartolom%C3%A9_de_las_Casas
The Church of the first two Centuries required that soldiers seeking baptism renounce their military commissions since the shedding of another’s blood was not compatible with Christian discipleship.
Source for this, please.
The foremost Catholic Biblical scholar who has dealt with the question of non-violence’s centrality in the New Testament is Fr. John L McKenzie. There is still dispute about the question of how the early Church regarded military service. Some hold that military service in the armies of Rome was avoided because of the idolatry involved. Others link the Church’s opposition to military service to such NT passages as Christ’s command to “Put away your sword…”
In any case from the Church’s early discouragement of military service as it can be seen in Canon 14 of Hippolytus: to writ:
“A Christian is not to become a soldier. A Christian must not become a soldier, unless he is compelled by a chief bearing the sword. He is not to burden himself with the sin of blood. But if he has shed blood, he is not to partake of the mysteries, unless he is purified by a punishment, tears, and wailing. He is not to come forward deceitfully but in the fear of God.”
to Pope Urban II’s call for the First Crusade a very significant doctrinal shift has taken place. No Early Church Father is to be found who with Augustine could uttered words like, '"…killing one’s enemy is acceptable as long as you love him while you are doing it".
Another shift occurred with Vatican II where the living of life non-violently was affirmed as a valid way of life not only for clerics but also for lay people. Before this, only the just war ethic of Ambrose and Augustine was seen as an acceptable Catholic way of deciding whether or not one could or should participate in a war.
Augustine’s just war doctrine imported by him and St. Ambrose from the pagan philosophy of stoicism remains the primary basis for making ethical judgments regarding war in today’s Church. But as you are no doubt well aware, recent popes have interpreted that doctrine so severely that it is hard to conceive of any modern war being adjudged as just. Unfortunately, at least in my experience, few American Catholic pastors have chosen to apply this interpretation of the doctrine to those wars that the United States has been involved in the last half century in their preaching and teaching. So the words of the Council’s documents however infallible the teachings of a Council might be consider can it seem, just as readily be ignored in the life of the Church.
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