Interesting excerpts:
In the Church – the People of God – only the sacred ministers, duly ordained after sufficient instruction and formation, may exercise the office of ''teaching, sanctifying and governing''. The lay faithful may, with a canonical mission from the Bishop, perform an ancillary ecclesial ministry of handing on the faith....there are certain Bishops – a very small number of them – who have been ordained without the Pontifical mandate and who have not asked for or have not yet obtained, the necessary legitimation. According to the doctrine of the Catholic Church, they are to be considered illegitimate, but validly ordained, as long as it is certain that they have received ordination from validly ordained Bishops and that the Catholic rite of episcopal ordination has been respected. Therefore, although not in communion with the Pope, they exercise their ministry validly in the administration of the sacraments, even if they do so illegitimately.
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Concerning Bishops whose consecrations took place without the pontifical mandate yet respecting the Catholic rite of episcopal ordination, the resulting problems must always be resolved in the light of the principles of Catholic doctrine. Their ordination – as I have already said – is illegitimate but valid, just as priestly ordinations conferred by them are valid, and sacraments administered by such Bishops and priests are likewise valid. Therefore the faithful, taking this into account, where the eucharistic celebration and the other sacraments are concerned, must, within the limits of the possible, seek Bishops and priests who are in communion with the Pope: nevertheless, where this cannot be achieved without grave inconvenience, they may, for the sake of their spiritual good, turn also to those who are not in communion with the Pope.
