In all the commentaries on Acts 10:44-48, you will find (and St. Luke and St. Peter themselves imply it) that Cornelius the catechumen (and both St. Augustine and St. Thomas also teach this) received the Holy Spirit before his Baptism. Thus, he received justification by Baptism of Desire and salvation after receiving the Sacrament. The question is, whether all who receive Baptism of Desire will also receive the Sacrament of Baptism? Here, St. Augustine answers yes, certainly, while St. Thomas answers, no, not necessarily. This question is not settled by the Magisterium. St. Augustine's position is theologically defensible. There is a text in the Gospel of Nicodemus which has come up in recent research that suggests the Ot patriarchs were actually baptized in some way before entering heaven. If so, that would support St. Augustine's position. In the Middle Ages, there was that decree of Pope Innocent that said one can hold the opinion of the Blessed Fathers. The text of St. Augustine cited there, that "Baptism is administered invisibly" to the person who desired and did not despise it is not clear whether it refers to Baptism of Desire or to the Sacrament of Baptism. At any rate, the Church certainly decreed that justified catechumens will be certainly saved, because Baptism will at least invisibly be administered to them.
Now, for those of you who agree with the Dimonds and think BOD is a "heresy", especially if you are sedevacantists, explain why Pope St. Pius X and Pope St. Pius V (and Pope Leo XIII who approved the Baltimore Catechism etc) did not "lose their office" upon approving it.
Catechism of Pope St. Pius X: "17 Q. Can the absence of Baptism be supplied in any other way? A. The absence of Baptism can be supplied by martyrdom, which is called Baptism of Blood, or by an act of perfect love of God, or of contrition, along with the desire, at least implicit, of Baptism, and this is called Baptism of Desire."
This clear and straightforward. Baptism of Desire certainly exists and the Dimonds are wrong and themselves outside the Church, where there is no hope or possibility of salvation, unless they return. Fr. Feeney's opinion as held by St. Benedict's centre has been declared permissible by the Church and requires closer study. It is an acceptable theological position but has not been absolutely proven yet.