Capt McQuigg said:
"Catholics, and Sedes are definitely Catholic because they adhere to the Catholic Faith."
In reference to modernism, does that sound familiar? That is syncretism.
Sedevacantists are just a modern brand of schismatics:
"And the Lord said: Simon, Simon, behold Satan hath desired to have you, that he may sift you as wheat:"
In three places does V1 assert that there is permanent succession. Also, it is a dogma of the Church:
"According to Christ's ordinance, Peter is to have successors in his Primacy over the whole Catholic Church and for all time."
And you can see the inherent dishonesty of sedevacantists, because they so obviously avoid as far as they can, dealing with this doctrine, because they will have a hard time twisting the terms "all time","permanent" and "forever" from their simple clear meaning.
In addition, I have never seen one straight answer from a sedevacantist in response to Our Lord's prohibition of their private judgement:
"But if thy brother shall offend against thee, go, and rebuke him between thee and him alone. If he shall hear thee, thou shalt gain thy brother.
And if he will not hear thee, take with thee one or two more: that in the mouth of two or three witnesses every word may stand. And if he will not hear them: tell the church. And if he will not hear the church, let him be to thee as the heathen and publican."
The requirement of the faith is to hold to the Chair of Peter and the keys and ex-cathedra promulgations. If a pontiff's private utterances are in error, they have no bind.
But sedevacantists are just a new set of pharisess as we see from their behavior, for commonly they are obsessive in searching out and broadcasting error (or so they judge, for especially, they do not know intention!):
"And they sent to him some of the Pharisees and of the Herodians; that they should catch him in his words."
Thus, is the verdict:
"Let no man seduce you, willing in humility, and religion of angels, walking in the things which he hath not seen, in vain puffed up by the sense of his flesh, And not holding the head, from which the whole body, by joints and bands, being supplied with nourishment and compacted, groweth unto the increase of God."
"Embracing that faithful word which is according to doctrine, that he may be able to exhort in sound doctrine, and to convince the gainsayers. For there are also many disobedient, vain talkers, and seducers: especially they who are of the circumcision:
Who must be reproved, who subvert whole houses"
"Even if that vicar were a devil incarnate, I must not defy him, but calmly lie down to rest on his bosom... He who rebels against our Father is condemned to death, for that which we do to him we do to Christ: we honor Christ if we honor the Pope; we dishonor Christ if we dishonor the Pope." (St Catherine to Letter to Bernabo Visconti)
"There are many who pretend they are friends of mine and protest that they love me, but in their hearts they hate me. How many so-called Christians imagine they are members of our Saviour when in reality they are his treacherous persecutors, for while they make the sign of the cross with their hand, in their hearts they are its enemies!" St Father Montfort - Letter to friends of the Cross