St. Jerome is said to have been rather cantankerous, with misanthropic tendencies. I have not read the exchange of letters between him and St. Augustine, so I don't know if they were as heated as they say it was. A master classicist with 'some familiarity' of Cicero, he also translated manuscripts of Sacred Scripture into Latin, forming the Vulgate. You can read more about him here.
It is also said, perhaps as an exaggeration, that his only friend was a lion.
The story of St. Jerome and the lion. (Something in Middle English.) Some paintings of Jerome with the lion.
After all, Jerome was friends with St. Gregory Naziansus. Life in life he joined a monastic community in Bethlehem. Whatever his natural disposition or temperament may have been like, since he is a saint one can be assured that he lived his life in conformance to charity. (Some are burdened with a more sour disposition than others, and therefore have greater obstacles to overcome in dealing with others.)
Well, I am in a Jerome mood once again--the vanity of the world's loves is on my mind. Maybe this will spur me on to concentrating on the thesis and getting it done...
Other Middle English texts. (Rochester) More on ME itself. Another link.