More Catholic teaching on flat earth.
The book of Ezekiel speaks of Jerusalem as in the middle of the earth, and all other parts of the world as set around the holy city. Throughout the "ages of faith" this was very generally accepted as the direct revelation from the Almighty regarding the earth's form. St. Jerome, the greatest authority of the early Church upon the Bible, declared, on the strength of this utterance of the prophet, that Jerusalem could be nowhere but at the earth's center; in the ninth century Archbishop Rabanus Maurus reiterated the same argument; in the eleventh century Hugh of St. Victor gave to the doctrine another scriptural demonstration; and Poe Urban, in his great sermon at Clermont urging the Franks to the crusade, declared, "Jerusalem is the middle point of the earth"; in the thirteenth century and ecclesiastical writer much in vogue, the monk Caesarious of Heisterbach declared, "As the heart in the midst of the body, so is Jerusalem situated in the midst of our in habited earth,--so it was that Christ was crucified at the center of the earth." Dante accepted this view of Jerusalem as a certainty, wedding it to immortal verse: and in the pious book of ascribed to Sir John Mandeville, so widely read in the Middle Ages, it is declared that Jerusalem is at the center of the world, and that a spear standing erect at the Holy Sepulchre casts no shadow at the equinox.
It is impossible that Jerusalem is the center of the earth if earth is a ball.
From St. Jerome to Pope Urban is 1000 years, which this teaching being held for so long a time, may constitute revelation.