I'd be interested in a citation of Iraneus, or at least a summary of his
reasoning on the four beasts.

On the iconology of the beasts, I think we may need to notice the differences
as well as the similarities. In Ezekiel's vision, he sees four living
creatures, each of whom has four faces, described as below.

Ezek 1:10  As for the likeness of their faces, they four had the face of a
man, and the face of a lion, on the right side: and they four had the face of
an ox on the left side; they four also had the face of an eagle.

In Revelation, there are several variations. The passage is about four
creatures, not four faces. Also, although this isn't widely recognized, we
aren't really told what the creatures look like. The first, for example, is
not a lion, but is only "like a lion," which has a somewhat different meaning
(lionlike?).

Rev 4:7  And the first beast was like a lion, and the second beast like a
calf, and the third beast had a face as a man, and the fourth beast was like
a flying eagle.

pat sloane