If you look at the Nicene and Post-Nicene Fathers collection, you will see a large number of sermons on books of the bible by John Chrysostom. The NPNF series was a pirate edition; it reprints the Oxford Movement translations, minus their notes, edited by Charles Marriot in the 1840’s and 50’s. You have to be struck by the sheer volume of these things. The sermons are of value to exegetes, of course. Pre-internet it was nearly impossible to access the Oxford Movement “Library of the Fathers” volumes. I suspect the notes would repay investigation.
But while turning photocopies into PDF’s, I came across an interesting article about the manuscripts of Chrysostom by J. W. Childers, Chrysostom’s Exegetical Homilies on the New Testament in Syriac Translation. This tells me that the earliest manuscripts of the Greek tradition are 10th or 11th century; not bad, but by no means early. I know that just listing medieval copies of Chrysostom takes volumes, so there is clearly a very great number of manuscripts. So it is a surprise to learn that no earlier copies exist.
But Childers article draws attention to the fact that the manuscripts of the Syriac version are far earlier. Thus for the Homilies on Matthew, the first 32 sermons (of 90) are preserved in four manuscripts, all from the Nitrian desert in Egypt, all of the 6th century. Another translation existed, referred to by Philoxenus of Mabbug in an anthology composed before 484 AD. The translations were made using the standard techniques of the 5th century, and show that the text of the Greek did not alter appreciably between the 5th and 10th centuries. The translations are insufficiently literal to be much use for text-critical concerns. But for the homilies on Paul’s letters the 6th and 7th century manuscripts are even more literal, and so can be used to correct the Greek.
The homilies were also translated from Syriac into Arabic, and catalogues of manuscripts invariably contain some. There is quite a section on these in Graf’s Geschichte der christlichen arabischen Literatur vol. 1. While the manuscripts may not be early, they will reflect a Syriac text that may be. It might also be interesting to wonder what exists in Armenian.