"Who Shall Ascend?" by Fr. Wathen has a lot about this subject beautifully explained, here is a brief snip:
Emphasis in the original
Predestination and Divine Election
The joy of the Early Church was not in the delusion that their salvation was an accomplished fact, the error of modern Evangelicals (and, apparently, Conciliar Catholics), but that they were in "the way of salvation," whereas those outside the communion of the faithful were not. In what exactly were the Christians rejoicing? In the fact that they had received the "adoption of sons of God." (Gal. 4:5). This is most beautifully expressed by St. Paul to the Ephesians.
We remind you again: Read these words as addressed to Catholics, converts to the Catholic Church, whose relatives and friends thought they had been seduced into an outlandish Jєωιѕн cult, who did their best to bring them back to their senses. (We are aware that we have considered these verses above; your attention here is invited to verses which bear witness to the Doctrine of Predestination, which must be seen as subsidiary to the Doctrine of Exclusive Salvation.)
Ephes. 1:3 - Blessed be the God and Father of our Lord Jesus Christ, who hath blessed us with spiritual blessings in heavenly places, in Christ:
4 - As he
chose us in him before the foundation of the world, that we should be holy and unspotted in his sight In charity.
5 - Who
hath predestinated us unto the adoption of children through Jesus Christ unto himself: according to the purpose of his will:
6 - Unto the praise of the glory of his grace, in which he hath
graced us in his beloved son.
7 - In whom we
have redemption through his blood, the remission of sins, according to the riches of his grace,
8 - Which hath superabounded in us in all wisdom and prudence,
9 - That he
might make known unto us the mystery of his will, according to his good pleasure, which he
hath purposed in him.
10 - In the dispensation of the fulness of times, to
reestablish all things In Christ that are in heaven and on earth, in him.
From these words we may draw the following conclusions:
1. With respect to the salvation of souls, we must recognize that all is achieved by divine initiative. We have italicized the verbs which describe the actions of God on our behalf.
2. Nothing could be more obvious than that St. Paul is exulting over the fact that the Almighty has selected certain ones out of the host of humanity for the "adoption of children."
3. St. Paul's realization is of "the great mystery," that whereas in the Old Testament NO ONE could attain Heaven, now, "in these days," "in the fulness of time," certain persons are able to do so, not only from among the Jєωs, but from among the Gentiles also. It is this fact that makes the age "the fulness of time."
4. Reflexively, we react by saying: But what about the rest? How is it just of God to choose some and to reject others? There can be but one answer to such a question, though admittedly it does not satisfy us, for it is not fully comprehensible, not, that is, as comprehensible as we would like. The answer is that those have been chosen, who were foreknown to accept their election. If others are rejected, it is because quite freely they reject the grace which would be for their peace.
5. If, therefore, anyone is chosen, the choice must begin in and with God, for no one can do anything for himself, unless God chooses him and enables him.
6. The joy of the predestinated, therefore, is that, of His infinite mercy, God has chosen us, through Jesus Christ. . . according to His good pleasure, in Whom He means "to re-establish all things in Christ." It is the holy Doctrine of Exclusive Salvation coupled with the mystery of Divine Election which explains the sustained, unremittant joyfulness of the Sacred Liturgy.
Fr. Wathen's book on CD (PDF format) can be ordered
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