Nevertheless, Barth was right that Przywara did not invent the analogia entis and that it has long been part of the Catholic tradition. Not only is it found in Augustine, specifically in Book XV of De Trinitate, which appears to have been the basis for the decision of the IV Lateran Council. It is also the implicit (but obvious) teaching of Aquinas, whom Przywara calls the teacher of the analogia entis, especially on account of Thomas’s teaching on secondary causes (since this teaching underscores, more so than NeoPlatonic models of exemplarism, including Augustine’s, the difference between God and creation). It is also, for that matter, the implicit teaching of Gregory of Nyssa, as is evident from Gregory’s reading of Exodus 3:14 and his corresponding understanding of the relation between Being and non-being. But it remained for centuries more of an implicit than an explicit teaching and thus stood in need of theological explication (precisely in keeping with Newman’s understanding of the development of doctrine, but here in terms of the Church’s understanding of creation). In fact, it does not appear as a terminus technicus until Cajetan and John of St. Thomas, and only thereafter, by way of Suárez’s Disputationes Metaphysicae, made its way into the Jesuit manuals in which Przywara first encountered it
Two thoughts arise from considering this passage:
First. As I and probably many other specialists writing on Scotus have pointed out, there are multiple senses of the "analogy being". There is a 'thick' sense, much like what is described in the passage quoted here, which involves dissimilarity-similarity, participation, causality, basically a whole cluster of metphysical notions. There is also a 'thin' sense, which is about the relations between terms and concepts. The thick sense includes the thin sense of analogy. Modern critics of Scotus generally don't distinguish these senses, and, without distinguishing where Henry's theory of analogy falls that Scotus rejects (and to be fair to modern theologians, many now seem to be aware that Scotus attacked Henry's theory of analogy and not Thomas'), assume Scotus rejects the analogia entis, simpliciter et totaliter, that is, that he throws out the thick sense of analogy.
Second. The claim here, backed by an article from 1970 (though, interestingly enough, the article is not by an author who is a medievalist, but apparently by another Przywara scholar) is that the usage of Analogia entis as a technical term is first found in Cajetan. Interestingly enough, the 17th c. Scotist theologian and philosopher Mastri made a similar claim, asserting that "the ancient scholastics wrote little about analogy" and that the debate over analogy began with Cajetan's book on the topic. One sees here the so-called tyranny of print: there was much discussion of analogy by authors such as Petrus Thomae who were never printed in the early days of the press, and so works such as the Quaestiones de ente (which dwarfs Cajetan's De nominum analogia) were lost to later ages. But John Betz and Mastri are both wrong. The usage of 'analogia entis' in both the thick and thin senses is found in the aforementioned Quaestiones de ente of Petrus Thomae, first printed in its entirety last year but written at Barcelona in 1325. This work also contains the first known mention of the Scotist school (Schola scotica). So the first professedly Scotist author is also the coiner of the Analogia entis? Given the widespread belief that Scotus himself and thus all his "progeny" rejected analogy, this is quite the historical irony. Moreover, given that Peter Thomae died in prison under charges of necromancy, perhaps the Analogy of Being is tainted, some attempted spell cast by Peter Thomae from across the ages; in the end perhaps it is, to paraphrase the (Latin) trial documents, a Nigromantical Principle.
For statements on analogy in PT, see Petrus Thomae, Quaestiones de ente q. 10 (thick analogy; see here). See also the same question for thin analogy, ed. me, p. 272: "Ad secundum et tertium et alias similes auctoritates dico quod explicant analogiam entis respectu substantiae et aliorum, sed haec analogia non repugnat verae univocationi." The edition records no variants here, but one wonders whether "aliorum" shouldn't be "accidentium".