four doctors of the church are (reading left to right) Saint Jerome, Saint
Gregory, Saint Ambrose and Saint Augustine.
St. Gregory (c 540 - 604) is the odd man out in this grouping, living a
hundred years later than the other three. He was pope from 590 - 604. He
was active and reforming. Calvin described him as 'the last good Pope',
which is perhaps a little harsh. As with the others, he was a
distinguished scholar; in England he is best known as the pope that sent
Saint Augustine of Canterbury on his mission to the English in 596.
Saint Ambrose of Milan (c 337 - 397) was, by popular acclaim and
highly unwillingly, elected Bishop of Milan in 374. At this point he was a
local politician and not even baptised. Eventually he agreed to
take on the
job. As Bishop, he lived an eventful life fighting heretics, particularly
supporters of the Arian heresy. (Wikipedia has a good article on Arianism
if you would like to know more.) These battles explain his attribute, the
knotted scourge, which has three strands to represent the Trinity.
and Jerome did not get on. Jerome suspected (probably with good reason)
that Ambrose had been involved in the church action to exile him from Rome
in 385. He never forgave him. It's just as
well that Vivarini painted them on opposite sides of the picture, or Jerome would be
knocking off Ambrose's mitre and bashing him over the head with his model
church, and Ambrose would be flogging Jerome with his scourge.
Saint Augustine (354 - 430) was Bishop of Hippo (in
present-day Algeria), and, rather like Ambrose, seems an unlikely person
to have become a bishop. In his earlier life he followed the highly
heretical belief system known as Manichaeism (yes, another one - you know
where to look). Like Jerome, his student days were rather wild, but
conversion brought him to (as he would see it) his senses. He never met
Jerome, but they did correspond. Augustine was a rather more tactful
letter-writer than Jerome, having great respect for the older man.
(Luckily for him, it seems, some of his more critical letters got lost in
the post, and Jerome only read copies of them much later.) There were
difficult moments at times, however. At the end of
Jerome's life they were on excellent terms.
Interestingly, images of Augustine bear no relation to
Augustine's probable actual appearance - he was a North African by birth.