As your third point you count the Word Greater; and as your fourth, To My God and your God. And indeed, if He had been called greater, and the word equal had not occurred, this might perhaps have been a point in their favour. But if we find both words clearly used what will these gentlemen have to say? How will it strengthen their argument? How will they reconcile the irreconcilable? For that the same thing should be at once greater than and equal to the same thing is an impossibility; and the evident solution is that the Greater refers to origination, while the Equal belongs to the Nature; and this we acknowledge with much good will. But perhaps some one else will back up our attack on your argument, and assert, that That which is from such a Cause is not inferior to that which has no Cause; for it would share the glory of the Unoriginate, because it is from the Unoriginate. And there is, besides, the Generation, which is to all men a matter so marvellous and of such Majesty. For to say that he is greater than the Son considered as man, is true indeed, but is no great thing. For what marvel is it if God is greater than man? Surely that is enough to say in answer to their talk about Greater.
-Gregory of Nazianzus, Oration 30.7, NPNF 2.7 (tr. by Browne and Swallow)
So, it appears that Gregory, contrary to Athanasius and many others, does not interpret the statements by Jesus concerning inferiority to the Father as referring to his incarnational state. Instead, “Greater” indicates something about generation, whereas their “equality” speaks to the kind of nature their share (i.e., the Father’s). Simply put, the Father is greater than the Son because he is the cause/source/arche of the Son, but the Son is equal to the Father because he has the same nature.