What did a medieval bishop earn?
About 2,600 pounds a year.
About $630,000 a month in today's gold.
A month of that pay weighs about as much as a five-litre bottle of water in gold.
"Canterbury has the finer stable, Winchester the deeper manger." The diocese is rich; you only spend it.
Where the money came from
A bishop lived on the estates that belonged to his see, not on a salary. The Archbishop of Canterbury's lands had been built up by the gifts of kings. In 791 Offa, King of Mercia, gave land at Otford in Kent, and the archbishops became lords of that manor. In 1086 Otford had six water mills and a large home farm worked by serfs, whose duties slowly turned into money payments. The archbishop kept a chain of houses and moved between them with a large following on a set timetable. Beside Canterbury Cathedral his palace had the second largest great hall in Britain, after Westminster Hall. In the late 1200s he collected about £2,600 a year from his estate. Lands could be taken away as well as given. Robert Winchelsey, archbishop from 1294 to 1313, would not let Edward I tax the clergy beyond set limits, and in 1297, when he still refused to pay, the king seized his lands; they came back that July, when the two made peace. Winchelsey later enlarged the manor house at Otford and died there. The archbishop was not the richest churchman. The Bishop of Winchester took about £4,000 a year and the Bishop of Worcester £1,200: Canterbury had more than twice Worcester's income, but Winchester had about one and a half times Canterbury's.
Sources: cambridge.org · en.wikipedia.org · en.wikipedia.org 2 · en.wikipedia.org 3
What a bishop's pay bought in 1350
a year's food for one adult: less than a day's pay
a knight's full armour: 2 days' pay
a warhorse: 2 weeks' pay
Harlech Castle: 3 years' pay, more than a whole year of it
the ransom of the King of France: 190 years' pay, more than a whole year of it
Every price of 1350, with its source, is on the prices page.