Authentication of s St. Paul’s Epistle to the Ephesians from a Catholic point of view are taken in three domains:
Authenticity
If one would only remember to whom the Epistle was addressed and on what occasion it was written, the objections raised against its Pauline authenticity could be readily answered.
Relation to other books of the New Testament
The letter to the Ephesians bears some resemblance to the Epistle to the Hebrews and the writings of St. Luke and St. John, in point of ideas and mode of expression, but no such resemblance is traceable in the great Pauline Epistles. Of course one of the Apostle's writings might have been utilized in these later documents but these similarities are too vague to establish a literary relationship. During the four years intervening between the Epistle to the Romans and that to the Ephesians, St. Paul had changed his headquarters and his line of work, and we behold him at Rome and Caesarea connected with new Christian centres. It is, therefore, easy to understand why his style should savour of the Christian language used in these later books, when we recall that their object has so much in common with the matter treated in the Epistle to the Ephesians. Whatever may now and then have been said on the subject, the same phenomenon is noticeable in the Epistle to the Colossians. If, indeed, the Epistle to the Ephesians agrees with the Acts in more instances than does the Epistle to the Colossians, it is because the two former have one identical object, namely, the constitution of the Church by the calling of the Jews and Gentiles.
The relationship between the Epistle to the Ephesians and I Peter is much closer. The letter to the Ephesians, unlike most of the Pauline Epistles, does not begin with an act of thanksgiving but with a hymn similar, even in its wording, to that which opens I Peter. Besides, both letters agree in certain typical expressions and in the description of the duties of the domestic life, which terminates in both with the same exhortation to combat the devil. With the majority of critics, we maintain the relationship between these letters to be literary. But I Peter was written last and consequently depends on the Epistle to the Ephesians; for instance, it alludes already to the persecution, at least as impending. Sylvanus, the Apostle's faithful companion, was St. Peter's secretary (1 Peter 5:12), and it is but natural that he should make use of a letter, recently written by St. Paul, on questions analogous to those which he himself had to treat, especially as according to us, those addressed in both of these Epistles are, for the greater part, identical (cf. 1 Peter 1:1).
The attacks made upon the authenticity of the Epistle to the Ephesians have been based mainly on its similarity to the Epistle to the Colossians, although some have maintained that the latter depends upon the former (Mayerhoff). In the opinion of Hitzig and Holtzmann, a forger living early in the second century and already imbued with Gnosticism used an authentic letter, written by Paul to the Colossians against the Judeo-Christians of the Apostolic Age, in composing the Epistle to the Ephesians, in conformity to which he himself subsequently revised the letter to the Colossians, giving it the form it has in the canon. De Wette and Ewald looked upon the Epistle to the Ephesians as a verbose amplification of the uncontroversial parts of the letter to the Colossians. However, it is only necessary to read first one of these documents and then the other, in order to see how exaggerated is this view. Von Soden finds a great difference between the two letters but nevertheless holds that several sections of the Epistle to the Ephesians are but a servile paraphrase of passages from the letter to the Colossians (Ephesians 3:1-9 and Colossians 1:23-27; Ephesians 5:21-6:9 and Colossians 3:18-4:1) and that still more frequently the later author follows a purely mechanical process by taking a single verse from the letter to the Colossians and using it to introduce and conclude, and serve as a frame, so to speak, for a statement of his own. Thus, he maintains that in Ephesians 4:25-31, the first words of verse 8 of Colossians 3, have served as an introduction (Ephesians 4:25) and the last words of the same verse as a conclusion (Ephesians 4:31). Evidently such methods could not be attributed to the Apostle himself. But, neither are we justified in ascribing them to the author of the Epistle to the Ephesians. For instance, the duties of husband and wife are well set forth in Colossians 3:18-19, but in these verses there is no comparison whatever between Christian marriage and that union of Christ with His Church such as characterizes the same exhortation in Ephesians 5:22 sq.; consequently, it would be very arbitrary to maintain the latter text to be a vulgar paraphrase of the former. In comparing the texts quoted, the phenomenon of framing, to which von Soden called attention, can be verified in a single passage (Ephesians 4:2-16, where verse 2 resembles Colossians 3:12 sq. and where verses 15-16 are like Colossians 11 and 19). In fact, throughout his entire exposition, the author of the Epistle to the Ephesians is constantly repeating ideas and even particular expressions that occur in the letter to the Colossians, and yet neither a servile imitation nor any one of the well-known offences to which plagiarists are liable, can be proved against him.
Moreover, it is chiefly in their hortatory part that these two letters are so remarkably alike and this is only natural if, at intervals of a few days or hours, the same author had to remind two distinct circles of readers of the same common duties of the Christian life. In the dogmatic part of these two Epistles there is a change of subject, treated with a different intention and in another tone. In the one instance we have a hymn running through three chapters and celebrating the call of both Jews and Gentiles and the union of all in the Church of Christ; and in the other, an exposition of Christ's dignity and of the adequacy of the means He vouchsafes us for the obtaining of our salvation, as also thanksgiving and especially prayers for those readers who are liable to misunderstand this doctrine. However, these two objects, Christ and the Church, are closely akin. Besides, if in his letter to the Ephesians, St. Paul reproduces the ideas set forth in that to the Colossians, it is certainly less astonishing than to find a like phenomenon in the Epistles to the Galatians and to the Romans, as it is very natural that the characteristic expressions used by the Apostle in the Epistle to the Colossians should appear in the letter to the Ephesians, since both were written at the same time. In fact it has been remarked that he is prone to repeat typical expressions he has one coined (cf. Zahn, Einleitung, I, p. 363 sq.). Briefly, we conclude with Sabatier that: "These two letters come to us from one and the same author who, when writing the one, had the other in mind and, when composing the second, had not forgotten the first." The vague allusions made in the Epistle to the Ephesians to some of the doctrinal questions treated in the Epistle to the Colossians, can be accounted for in this manner, even though these questions were never proposed by those to whom the former Epistle was addressed.
Difficulties arising from the form and doctrines
The denial of the Pauline authenticity of the Epistle to the Ephesians is based on the special characteristics of the Epistle from the viewpoint of style as well as of doctrine, and, while differing from those of the great Pauline Epistles, these characteristics although more marked, resemble those of the letter to the Colossians. But we have already dwelt upon them at sufficient length.
The circumstances under which the Apostle must have written the Epistle to the Ephesians seem to account for the development of the doctrine and the remarkable change of style. During his two years' captivity in Caesarea, Paul could not exercise his Apostolic functions, and in Rome, although allowed more liberty, he could not preach the Gospel outside of the house in which he was held prisoner. Hence he must have made up for his want of external activity by a more profound meditation on "his Gospel". The theology of justification, of the Law, and of the conditions essential to salvation, he had already brought to perfection, having systematized it in the Epistle to the Romans and, although keeping it in view, he did not require to develop it any further. In his Epistle to the Romans (viii-xi, xvi, 25-27) he had come to the investigation of the eternal counsels of Providence concerning the salvation of men and had expounded, as it were, a philosophy of the religious history of mankind of which Christ was the centre, as indeed He had always been the central object of St. Paul's faith. Thus, it was on Christ Himself that the solitary meditations of the Apostle were concentrated; in the quiet of his prison he was to develop, by dint of personal intellectual labour and with the aid of new revelations, this first revelation received when "it pleased God to reveal His Son in him". He was, moreover, urged by the news brought him from time to time by some of his disciples, as, for instance, by Epaphras, that, in certain churches, errors were being propagated which tended to lessen the role and the dignity of Christ, by setting up against Him other intermediaries in the work of salvation. On the other hand, separated from the faithful and having no longer to travel constantly from one church to another, the Apostle was able to embrace in one sweeping glance all the Christians scattered throughout the world. While he resided in the centre of the immense Roman Empire which, in its unity, comprised the world, it was the one universal Church of Christ, the fulfilment of the mysterious decrees revealed to him, the Church in which it had been his privilege to bring together Jews and pagans, that presented itself to him for contemplation.
These subjects of habitual meditation are naturally introduced in the letters that he had to write at that time. To the Colossians he speaks of Christ's dignity; to the Ephesians, and we have seen why, of the unity of the Church. But in these Epistles, Paul addresses those who are unknown to him; he no longer needs, as in preceding letters, to combat theories which undermined the very foundation of the work and to refute enemies who, in their hatred, attacked him personally. Accordingly, there is no further occasion to use the serried argumentation with which he not only overthrew the arguments of his adversaries but turned them to the latters' confusion. There is more question of setting forth the sublime considerations with which he is filled than of discussions. Then, ideas so crowd upon him that his pen is overtaxed; his sentences teem with synonyms and qualifying epithets and keep taking on new propositions, thus losing the sharpness and vigour of controversy and assuming the ample proportions of a hymn of adoration. Hence we can understand why, in these letters, Paul's style grows dull and sluggish and why the literary composition differs so widely from that of the first Epistles. When writing to the Colossians he at least had one particular church to deal with and certain errors to refute, whereas, in the Epistle to the Ephesians, he addressed himself at one and the same time to a group of unknown churches of which he had received but vague information. There was nothing concrete in this and the Apostle was left entirely to himself and to his own meditations. This is the reason why the special characteristics already indicated in the Epistle to the Colossians appear even more pronounced in that to the Ephesians, particularly in the dogmatic part.
Tradition
If we thus keep in mind the circumstances under which Paul wrote both of these letters, their peculiar character seems no obstacle to their Pauline authenticity. Therefore, the testimony which, in their inscriptions (Colossians 1:1; Ephesians 1:1), they themselves render to this authenticity and the very ancient tradition which unanimously attributes them to the Apostle preserve all their force. From the traditional viewpoint the Epistle to the Ephesians is in the same class as the best attested letters of St. Paul. Used in the First Epistle of St. Peter, in the Epistle of St. Polycarp, in the works of St. Justin, perhaps in the Didache and I Clement, it appears to have been already well known towards the end of the first century. Marcion and St. Irenæus ascribe it to St. Paul and it seems that St. Ignatius, when writing to the Ephesians, had already made use of it as Pauline. It is also to be noted that if the authenticity of this Epistle has been denied by most of the liberal critics since Schleiermacher's day, it is nevertheless conceded by many modern critics, Protestants among them, and held at least as probable by Harnack and Julicher. In fact the day seems to be approaching when the whole world will recognize as the work of St. Paul, this Epistle to the Ephesians, of which St. John Chrysostom admired the sublime sentences and doctrines: noematon meste . . . . . . . hypselon kai dogmaton.