The Epistle of Barnabas is not part of the New Testament canon, though it was included in Codex Sinaiticus and Origen referred to it as a catholic epistle! Eusebius and Jerome, however, categorized it as a disputed writing and it was classed with the apocrypha.
Modern scholars label it “anonymous,” even though early church tradition (Clement of Alexandria, Origen, Jerome, Serapion of Thmuys, Codex Sinaiticus) attributes it to “Barnabas.” This attribution, along with its inclusion in Codex Sinaiticus, Codex Hierosolymitanus, and Codex Corbeiensis, appears to point to a belief that the Barnabas described in the book of Acts is the Barnabas in view. Modern scholars cite internal evidence against the view that Barnabas wrote the epistle, but it seems to me that this internal evidence is not altogether conclusive. As for it being “anonymous,” it is “anonymous” in the same way that the Gospels are “anonymous,” and I think Martin Hengel has shown pretty conclusively that these Gospels never would have been circulated without a title, nor would the titles of the Gospels be so uniform if they were not original (or at least practically original) to the first production of the respective Gospels. So, I think it is as plausible as not that the document we know as The Epistle of Barnabas was written by the sometime companion of Paul in Acts.
All these prefatory comments prepare the way for what I am about to say about the way that Barnabas cites the “Let us make man in our image” statement in Genesis 1:26–28. Twice in the Epistle of Barnabas, at 5:5 and at 6:12, the “let us” statements are cited as words spoken by the Father to the Son.
There is yet this also, my brethren; if the Lord endured to suffer
for our souls, though He was Lord of the whole world, unto whom God
said from the foundation of the world, Let us make man after our
image and likeness, how then did He endure to suffer at the hand
For the scripture saith concerning us, how He saith to the Son; Let
us make man after our image and after our likeness, and let them
rule over the beasts of the earth and the fowls of the heaven and
the fishes of the sea. And the Lord said when He saw the fair
creation of us men; Increase and multiply and fill the earth.
These words refer to the Son.
I have heard people I love and respect describe the first person plurals here as “plurals of majesty,” and this is a valid category in Hebrew grammar (at least it’s in GKC). But I wonder if what we have in Barnabas 5:5 and 6:12 doesn’t fall nicely in line with early Christian “wisdom Christology”—“wisdom” pointing to God’s work in creation (cf. Prov 8:22–31), and “wisdom Christology” pointing to the consistent teaching of the NT that God created through the Son (see, e.g., John 1:3; Col 1:16; Heb 1:2).
If this is correct, then just as John, Paul, and the author of Hebrews speak of Jesus as the agent of creation, the Epistle of Barnabas speaks of Jesus as active in creation and reads Genesis 1 in a way that comports with early Christian wisdom Christology.
In the light of progressive revelation, this early Christian writing, perhaps written in the first century (but probably no later than AD 135), perhaps written by a companion of Paul, reads the words of Genesis, “Let us make man in our image,” as words spoken by the Father to the Son. I have no quarrel with such a reading.