...can we simply say 'forgive them for they know not what they do'...or can we paraphrase that;  they thought so at the time.  Nothing is static outside of church thinking.  Burke is enmeshed in church legalisms, beginning with acceptance of beliefs posited as truths.  We have grown with time in learning, knowing and discovery, what once was held firmly can now be regarded lacking in substance.  Disputation is NOT that Burke does not possess expertise in canon law, the concern is the legalistic, rigid adherence to a static formula, which might not hold true with what we know contrasted with belief held as true.