With this in mind, we turn to the oldest Christian homily (sermon) in existence:
So, then, brethren, if we do the will of our Father God, we shall be members of the first church, the spiritual,— that which was created before sun and moon; but if we shall not do the will of the Lord, we shall come under the Scripture which says, "My house became a den of robbers." So, then, let us elect to belong to the church of life, that we may be saved. I think not that you are ignorant that the living church is the body of Christ (for the Scripture, says, "God created man male and female;" the male is Christ, the female the church,) and that the Books and the Apostles teach that the church is not of the present, but from the beginning. For it was spiritual, as was also our Jesus, and was made manifest at the end of the days in order to save you. The church being spiritual, was made manifest in the flesh of Christ, signifying to us that if any one of us shall preserve it in the flesh and corrupt it not, he shall receive it in the Holy Spirit. For this flesh is the type of the spirit; no one, therefore, having corrupted the type, will receive afterwards the antitype. Therefore is it, then, that He says, brethren, "Preserve the flesh, that you may become partakers of the spirit." If we say that the flesh is the church and the spirit Christ, then it follows that he who shall offer outrage to the flesh is guilty of outrage on the church. Such an one, therefore, will not partake of the spirit, which is Christ. Such is the life and immortality, which this flesh may afterwards receive, the Holy Spirit cleaving to it; and no one can either express or utter what things the Lord has prepared for His elect. (ch 14)For pseudo Clement, (hereafter referred to as Clement for the sake of brevity), the Church pre-exists its earthly manifestation as an invisible, spiritual form and is embodied in the Church as flesh. If Clement is right, and if the Incarnation is the correct starting point for developing true ecclesiology, then it would not suffice to say, as many do, that the spiritual Church is only clothed in the visible Church just as it would not have been enough to say Jesus was merely clothed in His physical Body. He was not a spirit animating a corpse -
The Word was made Flesh and dwelt among us.Likewise then, the spiritual Church, the bride of Christ, became a physical reality – embodied, not clothed, in the Church as she sojourns on earth. This second century homilist, whose hearers would have already been exposed to Gnosticism (particularly Docetism), would find it necessary to embellish this point a bit; to show that as Christ was truly made Flesh, so the Church was truly made physical – visible. So much was the visible reality united with the spiritual Bride and so much was the Church the mystical Body of Christ that to dishonor her meant to dishonor Christ. Now, if you dishonor my wife, you dishonor me, but something different is going on here. To dishonor the Church was a direct dishonor to Christ it seems.
Finally, the Church is introduced in this homily as mother:
In that He said,The gender of the Church is important for understanding her spousal relationship with Christ and with her maternity in relation to the believer. Bearing all this in mind, that the Incarnation is the proper framework for ecclesiology, that the Church is the mystical Body of Christ and that she is properly understood as female being, both the Bride of Christ and mother of the believer, it stands to reason that any ecclesiology which fails to deliver the Church in this way is heretical in nature.Rejoice, you barren that bearest not,He referred to us, for our church was barren before that children were given to her.(ch 2)
Now all ecclesiologies speak of the Church as visible or visibly manifested, all of them speak of her as the mystical body of Christ and all speak of her as His bride. Most are comfortable calling her the mother of the believer. But there is as big of a difference between the Catholic and non-Catholic in this regard as there was with the Catholic and the Gnostic. Gnostics were comfortable using a lot of the same language as Catholics in the second century – but they didn't believe the same things. As Irenaeus explains, they would be happy admitting that Mary was involved in the birth of Jesus (how could they deny it?) but would stop short of understanding her role as anything greater than as a tube when water is passed through it. Some Gnostics would be happy using the term “Body of Christ” with the caveat that it was only body as a shell – not truly His. These same Gnostics, we may assert with confidence, would be entirely at home to speak of a visible Church so long as it was maintained as only a visible manifestation animated by something which was only spiritual in essence.
For these reasons, it must be maintained that the Catholic Church, and she alone as a unified body which extends to the apostles, can rightly call herself “the Church”. She alone maintains full fidelity to Incarnational ecclesiology. Bryan Cross has written on this subject two posts which come highly recommended here and here.