Here is the history of the doctrine of justification.
No theologian or Christian figure of any note believed in forensic, imputed justification until Luther and Calvin came onto the scene of Church history in the 16th century. It is simply implausible and incredible (and unbiblical: Matthew 16:18, John 14:26) to think that a theological concept considered so absolutely crucial by Protestants could have been lost immediately after the Apostles and for fifteen centuries thereafter. I have seen how Protestant notions of justification, absolute assurance of a salvation which can't be lost, eradication of free will, double predestination, and so forth, are unbiblical.
In the late first century and early second, St. Clement of Rome speaks of "being justified by works and not by words," (1) just as St. James does. Likewise, St. Ignatius of Antioch warns against "desertion" and describes works as "deposited withholdings" which will accumulate "back-pay." (2) Thus, the concepts of merit and loss of salvation are delineated very early on.
In the second century, St. Justin Martyr refers to "the merit of each man's actions," upholds free will, (3) and directly denies imputed justification. (4) St. Theophilus (5) and St. Irenaeus (6) discuss merit and good works with regard to salvation, as does Tertullian, around 204 A.D. (7)
In the third century, St. Clement of Alexandria defines baptism as "a washing by which we are cleansed of sins," (8) and denies "faith alone." (9) Origen (10) and St. Cyprian (11) espouse good works and merit, and the latter expressly affirms baptismal regeneration. (12)
In the fourth century, St. Gregory of Nyssa writes, "Faith without works of justice is not sufficient for salvation." (13) St. John Chrysostom makes the same denial of "faith alone" (14) and teaches infused justification: "He has not only delivered us from sins, but has made us lovable." (15) St. Ambrose makes works (and merit) the scale upon which our eternal destiny will be weighed. (16) St. Jerome condemns "faith alone." (17)
In the early fifth century, St. Augustine repudiates the Calvinist ideas of Unconditional Election and Irresistible Grace: "He does not justify you without your willing it." (18) He teaches an initial justification (19) which enables the Christian to perform meritorious good works, (20) order to work out their salvation, as St. Paul taught. Around 421, he elaborated his view of infused justification: Grace makes a man entirely new . . . it even renews a man perfectly, to the extent that it achieves his deliverance from absolutely all sins. (21)
And a few years before his death, he warned of the possible loss of one's salvation: If someone already regenerate and justified should, of his own will, relapse into his evil life, certainly that man cannot say: 'I have not received'; because he lost the grace he received from God and by his own free choice went to evil. (22)
This utterly contradicts Calvinism's Perseverance of the Saints as well as Irresistible Grace. St. Augustine was no Protestant, and most assuredly not a Calvinist!
The Second Council of Orange in 529 (23) condemned the heresies of Pelagianism and Semi-Pelagianism (which St. Augustine had already done a century earlier). Pelagianism denied Original Sin and regarded grace as within man's natural capacities. Semi-Pelagianism made man primarily responsible for his own salvation and denigrated the necessity of God's enabling grace. The Council made many binding definitions of grace and salvation which may be quite surprising to many Protestants, who want to accuse the Catholic Church of the same heresies which it anathematized fourteen centuries ago. The Catholic Church fully agrees with Holy Scripture that faith, the subjective condition of justification, is a gift of God (Ephesians 2:8 ff., John 6:66, Hebrews 12:12, Philippians 1:6, 1:29, 1 Corinthians 4:7). This was the emphasis of 2nd Orange. (24)
1. 1st Clement (to the Corinthians), 30:3, 31:2, 32:3-4, 33:1-2,7, 34:1-3. From Lightfoot, Joseph B. & J.R. Harmer, tr., The Apostolic Fathers, 2nd ed., ed. & rev. by Michael W. Holmes, Grand Rapids, MI: Baker Book House, 1989 (1st ed. 1891), 45.
2. Letter to Polycarp, 6,2. From Jurgens, FEF, vol. 1, 26.
3. First Apology, 43. Jurgens, FEF, vol. 1, 53.
4. Dialogue With Trypho the Jew, 141. Jurgens, FEF, vol. 1, 62-63.
5. To Autolycus, 1,14.
6. Against Heresies, 4,37,7.
7. Repentance, 2,11j 6,4.
8. The Instructor of Children, 1,6,26,1-2. Jurgens, FEF, vol. 1, 178.
9. Miscellanies (Stromateis), 6,14,108,4-5. Jurgens, FEF, vol. 1, 184.
10. Commentaries on John, 19,6.
11. Works and Almsgiving, 14.
12. To Donatus, 4. ne 13. Homilies on Ecclesiastes, 8. Jurgens, FEF, vol. 2, 46.
14. Homilies on the Gospel of John, 31,1.
15. Homilies on Ephesians, 1,3. Jurgens, FEF, vol. 2, 120.
16. Letter to Constantius, a Bishop, 2,16; The Duties of the Clergy, 1,15,57.
17. Commentaries on Galatians, 2,3,11.
18. Sermons, 169,13. Jurgens, FEF, vol. 3, 29.
19. Various Questions to Simplician, 1,2,2.
20.Various Questions to Simplician, 1,2,21.
21. Against Julian, Defender of Pelagianism, 6,13,40. Jurgens, FEF, vol. 3, 146.
22. Admonition and Grace, 6,9. Jurgens, FEF, vol. 3, 157.
23. The Second Council of Orange was not an ecumenical, or General Council, but is solemnly authoritative for all Catholics due to the confirmation of Pope Boniface II (Papal Bull: Per Filium Nostrum, January 25, 531).
24. Some of the more important decrees of the Second Council of Orange in 529:
Canon 3: If anyone says that the grace of God can be conferred in answer to man's petition, but that the petition itself is not due to the action of grace, he contradicts the prophet Isaiah and the Apostle, who both say: 'I was found by them that did not seek me, I appeared openly to them that ask not after me' (Romans 10:20, Isaiah 15:1). {In Bouyer, Louis, The Spirit and Forms of Protestantism, tr. A.V. Littledale, London: Harvill Press, 1956, 67}.
Canon 4: If anyone contends that God waits for our will so we may be cleansed from sin - and does not admit that the very fact that we even will to be cleansed comes in us by the infusion and work of the Holy Spirit, he resists the same Holy Spirit. {In Most, William G., Catholic Apologetics Today, Rockford, IL: TAN Books and Publishers, 1986, 110}.
Canon 5: If anybody says that the . . . beginning of Faith and the Act of Faith itself . . . is in us naturally and not by a gift of grace that is by the inspiration of the Holy Ghost, he is opposed to Apostolic teaching. {In Ott, Ludwig, Fundamentals of Catholic Dogma, tr. Patrick Lynch, Rockford, IL: TAN Books and Publishers, 1974 {orig. 1952 in German}, 230}.
Canon 6: If anyone says that God has mercy on us when, without his grace, we believe, will, desire, strive, work, watch, study, ask, seek, knock, and does not confess that we believe, will, and are enabled to do all this in the way we ought, by the infusion and inspiration of the Holy Spirit within us; or makes the help of grace depend on the humility or obedience of man, rather than ascribing such humility and obedience to the free gift of grace; he goes counter to the Apostle, who says, 'What hast thou that thou hast not received?' and 'By the grace of God I am what I am' (1 Corinthians 4:7 and 15:10). {Bouyer, 67-68}.
Canon 7: If anyone asserts that we can, by our natural powers, think as we ought, or choose any good pertaining to the salvation of eternal life, that is, consent to salvation or to the message of the Gospel, without the illumination and inspiration of the Holy Spirit . . . he is misled by a heretical spirit, not understanding what the voice of God says in the Gospel, 'Without me you can do nothing' (John 15:5), nor the words of the Apostle, 'Not that we are sufficient to think anything of ourselves, as of ourselves, but our sufficiency is from God' (2 Corinthians 3:5). {Bouyer, 68}.
Canon 9: As often as we do good God operates in us and with us, so that we may operate. {Ott, 229}.
Canon 13: Free will, weakened in the person of the first man, can be repaired only by the grace of Baptism . . . [cites Jn 8:36]. {Bouyer, 68}.
Canon 20: Man does no good except that which God brings about that man performs . . . {Ott, 229}.
Canon 25: In a word, to love God is a gift of God. He, yet unloved, loves us and gave us the power to love . . . Through the sin of the first man, the free will is so weakened and warped, that no one thereafter can either love God as he ought, or believe in God, or do good for the sake of God, unless moved, previously, by the grace of the divine mercy . . . In every good work that we do, it is not we who have the initiative, aided, subsequently, by the mercy of God, but that he begins by inspiring faith and love towards him, without any prior merit of ours. {Bouyer, 69}.
So on to the next point...right?