This is a very good question There are a couple of different ways we can look at this authority.
The first and most common view would be that, because she is protected by the Holy Spirit, the Church will never “bind or loose” anything on earth that has not aleady been bound or loosed in heaven. This would preclude it’s ever changing the “Truth” that is Christ.
**No argument there. We do still have to keep in mind that the Risen Christ identified that He had more things to tell us, so our understanding of the “Truth” must have a certain amount of flexibility. **
The Second way is that God, in His mercy, will accept whatever the Church binds or looses as the measure by which He will judge us. Even if such might involve a certain amount of error. We find support for this in Matthew where Jesus says, “all that they tell you, do and observe” because “The Scribes and the Pharisees sit in Moses’ seat”. (Matthew 23:2-3). Jesus goes on to say, " do as they say but do not do as they do".
We all know how Jesus felt about how the Scribes and Pharasees behaved and yet He tells the disciples to obey there teachings.
Personally I believe that it is a combination of these two positions.
The Church, as a whole cannot teach error. It cannot do so because of the promised protection of the Holy Spirit who leads Her into all Truth. Additionally the way in which teachings are developed and promulgated makes it fairly impossible to make a fundemental change in any moral Truth.
However this does not preclude the possibility of erroneous understanding, teaching, advise etc by individuals within the Church. For instance, say a person goes to their confessor and discusses some matter of morals and receives bad advise. They have no reason to doubt their confessor and they act upon the this advise which causes them to continue in some sin. The confessor may have some culpability in giving the bad advise, but the person who, in good conscience, has little or none. If such a one dies without having this error rectified, Mt 23:2-3 indicates that they will be judged rightious based on their honest attempts to follow God in His Church rather than being judged lacking based on what they, “should have known”.
Some folks ‘shop’ for individuals that will allow them - or appear to allow them - to do what they want to do, regardless of propriety of the action. This can be seen in patients who ‘shop’ for doctors to get more drugs to maintain a habit… or with priests who may not be told the entire story and give counsel based on what they are told by the person apparently seeking guidance but, really seeking license.
So at the highest levels of Church teaching Moral relativism is unlikely to creep in. At the lower levels, where indiviual cases must be looked at, in the confessional and elsewhere, certainly some “relativism” could come into play.
Peace
James
. In order to make any kind of decision, a judgment must be made. While none of the Popes can judge the soul - they make judgments about morally deficient actions. For example, not contained in the Ten Comandments is the Catholic Church’s teaching about abstaining from meat on Ash Wednesday and (usually) all of the Fridays in Lent (The Feast of St. Joseph fell on a Friday this year and there was an exemption). So, here we have a clear example of binding and losing - and this is concerning grave matter.
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