What about the Old Testament “saints”? We venerate the prophets and patriarchs of the Old Testament as saints in heaven. The Carmelites, for example, celebrate the feast of St. Elijah the Prophet. On the Church’s calendar, December 24 is an optional feast of Adam and Eve, our First Parents (or at least it was in the past). Scripture teaches, and the Extraordinary Form of the mass confirms, that Abraham is our father in faith. In the Eastern Churches, in particular, many churches are dedicated to this or that Old Testament prophet. NONE of these old testament saints were baptized in the Christian sacramental sense. It is the tradition of the Church that Our Lord descended into Hades and opened the gates to heaven, allowing the righteous who had eagerly awaited his coming to enter into eternal bliss. Even St. John the Baptist, the only saint (besides Our Lady) whose nativity is celebrated in the Church, was never sacramentally baptized, yet we know from Scripture that he was filled wih the Holy Spirit even in the womb. If they were saved without baptism, why can’t God make other exceptions? agree Genesis315 - God is capable of removing original sin through means unknown to the Church.
Code:
CATECHISM OF POPE SAINT PIUS X
The Church in Particular
8 Q. What is the Catholic Church?
A. The Catholic Church is the Union or Congregation of all the baptised who, still living on earth, profess the same Faith and the same Law of Jesus Christ, participate in the same Sacraments, and obey their lawful Pastors, particularly the Roman Pontiff.
9 Q. State distinctly what is necessary to be a member of the Church?
A. To be a member of the Church it is necessary to be baptised, to believe and profess the teaching of Jesus Christ, to participate in the same Sacraments, and to acknowledge the Pope and the other lawful pastors of the Church.
…
23 Q. In what does the Body of the Church consist?
A. The Body of the Church consists in her external and visible aspect, that is, in the association of her members, in her worship, in her teaching-power and in her external rule and government.
24 Q. To be saved, is it enough to be any sort of member of the Catholic Church?
A. No, to be saved it is not enough to be any sort of member of the Catholic Church; it is necessary to be a living member.
27 Q. Can one be saved outside the Catholic, Apostolic and Roman Church?
A. No, no one can be saved outside the Catholic, Apostolic Roman Church, just as no one could be saved from the flood outside the Ark of Noah, which was a figure of the Church.
28 Q. How, then, were the Patriarchs of old, the Prophets, and the other just men of the Old Testament, saved?
A. The just of the Old Testament were saved in virtue of the faith they had in Christ to come, by means of which they spiritually belonged to the Church.
If one has perfect charity and perfect contrition for his sins, then he can be saved through a baptism of desire. Prior to Christ’s coming, this was the means by which the OT saints were saved coupled with their supernatural faith in God and in Christ to come (whether this faith in the coming Redeemer was explicit or implicit is a matter of speculation). It was much more difficult to be saved prior to the coming of Christ than it is now, as perfect contrition and perfect charity are not easy to come by. (See the Catechism from the Council of Trent on why Christ instituted the sacrament of Penance.) Hope this helps.