Round earthers have to explain more than lack of curvature, curved water surface and ships that don't disappear behind the non existent curve.

And how do round earthers explain how so many people have stumbled off the edge of the earth?
*Disclaimer: I apologize if this question makes anybody look stupid.

The Church ONLY taught geocentric flat earth.

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False. The Church never taught the shape of the earth.
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False. The Church never taught the shape of the earth.
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Lactentius in the Divine institutes, Chapter 24 :

they thought that the world is round like a ball, and
they fancied that the heaven revolves in accordance with the motion of
the heavenly bodies; and thus that the stars and sun, when they have
set, by the very rapidity of the motion of the world are borne back to
the east. Therefore they both constructed brazen orbs, as though after
the figure of the world, and engraved upon them certain monstrous
images, which they said were constellations.
....I am at a loss what to say respecting those who, when they have
once erred, consistently persevere in their folly, and defend one vain
thing by another; but that I sometimes imagine that they either discuss
philosophy for the sake of a jest, or purposely and knowingly undertake
to defend falsehoods, as if to exercise or display their talents on
false subjects.

On June 22, the Holy Office formally condemns Galileo for heresy: 

“We say, pronounce, sentence and declare that you, the said Galileo...have rendered yourself in the judgment of this Holy office vehemently suspected of heresy, namely, of having believed and held the doctrine which is false and contrary to the Sacred and Divine Scriptures, that the sun is the center of the world and does not move from east to west and that the earth moves and is not the center of the world...after it has been declared and defined as contrary to Holy Scripture...From which we are content that you be absolved, provided that...you abjure, curse, and detest before us the aforesaid errors and heresies and every other error and heresy contrary to the Catholic and Apostolic Roman Church.”  Pope Urban VIII took full responsibility for the condemnation of Galileo by enforcing “in forma communi” the Congregation’s prohibitions against books holding the Copernican system as truth.
Reference: Exorciser le spectre de Galilée - Abbe Philippe Marcille, Editions du Sel, 2014, pp 40 and scripturecatholic.com

St. John Chrysostom Commentary on the Hebrews 8:1

“Where are those who say that the heaven is in motion? Where are those who think it is spherical? For both these opinions are here swept away.”
Quoted by Cosmas.


St. Jerome, Commentary on Isaiah

God "[had] established the great mass of the land and had gathered it together above the seas and rivers, so that the heaviest element [earth] hangs over the lighter weight waters by the will of God, who like a king sits above the circle of the earth. There are some who assert that this mass is like a point and globe...What, then, will the land be over ...?"



From the Pontifical Decrees Against The Doctrine The Earth’s Movement by Rev. William W. Roberts

"Since it has come to the knowledge of the above-named Holy Congregation that the false Pythagorean doctrine, [See: Pythagoras] altogether opposed to the divine Scripture, on the mobility of the earth and the immobility of the sun...this Congregation has decreed that the said books...be suspended till they are corrected; but that the book of Father Paul Antony Foscarini the Carmelite be altogether prohibited and condemned, and all other books that teach the same thing; as the present decree respectively prohibits, condemns, and suspends all...." (pp.56, 57)

[Why is this significant? The idea that the world was a sphere has been around a long time, but Pythagoras was one of the first to come up with it. This quote shows that the church was not only aware of the round earth error but also that its source was pythagoras]


Methodius:
“Resuming  then,  let  us  first  lay  bare,  in  speaking of  those  things  according  to  our  power,  the imposture  of  those  who  boast  as  though  they  alone  had  comprehended  from  what  forms  the  heaven  is arranged,  in  accordance  with  the  hypothesis  of  the  Chaldeans  and  Egyptians.  For *they*  say  that  the circuмference  of  the  world  is  likened  to  the  turnings  of  a  well-rounded  globe,  the  earth  having  a central  point.  For  its  outline  being  spherical,  it  is  necessary,  they  say,  since  there  are  the  same  distances of  the  parts,  that  the  earth  should  be  the  center  of  the  universe,  around  which  as  being  older,  the  heaven is  whirling.  For  if  a  circuмference  is  described  from  the  central  point,  which  seems  to  be  a  circle,  -  for  it is  impossible  for  a  circle  to  be  described  without  a  point,  and  it  is  impossible  for  a  circle  to  be  without  a point,  -  surely  the  earth  consisted  before  all,  they  say,  in  a  state  of  chaos  and  disorganization.  Now certainly  the  wretched  ones  were  overwhelmed  in  the  chaos  of  error,  “because  that,  when  they  knew  God, they  glorified  Him  not  as  God,

TheophilusTheophilus writing to Autolycus following the LXX says:
The heaven, therefore, being dome-shaped covering, comprehended matter which was like a clod. And so another prophet, Isaiah by name, spoke in these words: It is God who made the heavens as a vault, and stretched them as a tent to dwell in.This heaven which we see has been called firmament, and to which half the water was taken up that it might serve for rains, and showers, and dews to mankind. And half the water was left on earth for rivers, and fountains, and seas (Schaff and Wace 1979, 2:100).
Theophilus interprets the "circle of the earth" as referring to the vault of heaven.
much more at
http://flatearthtrads.forumga.net/t60-pertinent-quotes-from-fathers-and-tradition

St. John Chrysostom

(considered a “doctor of the Church”, bishop of Antioch, archbishop of Constantinople in 398) –opposed the earth’s sphericity based on Scripture. Regularly refers to the Earth having four corners as the Bible does in his sermons. For example, the following quotations come from Homilies Against the Jєωs: “every corner of the earth”, “her action is known in every corner of the earth”, “every corner of the earth seen by the sun” [27] Exerted his influence against a spherical earth. [2] He is quoted by Kosmas (Cosmas) as stating “Where are those who say that the heaven is in motion? Where are those who think it is spherical? For both these opinions are here swept away.”(in commenting on Hebrews 8:1.)Knew that truly ending the ‘heretical’ study of the Greeks meant wiping out Greek writings – happily declared, “Every trace of the old philosophy and literature of the ancient world has vanished from the face of the earth.”
In his“Homily 2, Trinity, Sophists, Philosophers”, Para 5, he takes pleasure in the fact that the Church is successfully silencing the Greeks – “And as for the writings of the Greeks, they are all put out and vanished, but this man’s shine brighter day by day. …since then the (doctrines) of Pythagoras and of Plato, which seemed before to prevail, have ceased to be spoken of, and most men do not know them even by name.” [77], [78] He continues to claim, “Pythagoras… practiced there ten thousand kinds of sorcery…. but by his magic tricks he deceived the foolish. And neglecting to teach men anything useful.” He then calls Pythagoras a “barbarian”!
Chrysostom was “definitely a strong fundamentalist if not an absolute Biblical literalist and he certainly seems to have believed the earth was flat. Like Tertullian, he was skeptical of any ‘pagan’ knowledge which seemed to cast doubt on any aspect of the Bible.

St. John Chrysostom

(considered a “doctor of the Church”, bishop of Antioch, archbishop of Constantinople in 398) –opposed the earth’s sphericity based on Scripture. Regularly refers to the Earth having four corners as the Bible does in his sermons. For example, the following quotations come from Homilies Against the Jєωs: “every corner of the earth”, “her action is known in every corner of the earth”, “every corner of the earth seen by the sun” [27] Exerted his influence against a spherical earth. [2] He is quoted by Kosmas (Cosmas) as stating “Where are those who say that the heaven is in motion? Where are those who think it is spherical? For both these opinions are here swept away.”(in commenting on Hebrews 8:1.)Knew that truly ending the ‘heretical’ study of the Greeks meant wiping out Greek writings – happily declared, “Every trace of the old philosophy and literature of the ancient world has vanished from the face of the earth.”
In his“Homily 2, Trinity, Sophists, Philosophers”, Para 5, he takes pleasure in the fact that the Church is successfully silencing the Greeks – “And as for the writings of the Greeks, they are all put out and vanished, but this man’s shine brighter day by day. …since then the (doctrines) of Pythagoras and of Plato, which seemed before to prevail, have ceased to be spoken of, and most men do not know them even by name.” [77], [78] He continues to claim, “Pythagoras… practiced there ten thousand kinds of sorcery…. but by his magic tricks he deceived the foolish. And neglecting to teach men anything useful.” He then calls Pythagoras a “barbarian”!
Chrysostom was “definitely a strong fundamentalist if not an absolute Biblical literalist and he certainly seems to have believed the earth was flat. Like Tertullian, he was skeptical of any ‘pagan’ knowledge which seemed to cast doubt on any aspect of the Bible.

Thank you for posting the above, Cera.

I've not heard of Cosmas before. But it seems, by the quotes above, that he was happy that the pagan Greek philosophy regarding the shape and supposed motion of the earth was losing ground. 

And that St. John Chrysostom, as is mentioned above, was also preaching against the doctrines of the pagans Pythagoras and Plato, saying, ...."Pythagoras....practiced there ten thousand kinds of sorcery....but by his majic tricks he deceived the foolish. And neglecting to teach men anything useful," and he also called Pythagoras a "Barbarian."

It's useful also to know, from what is mentioned in the above post, that Chrysostom seemd to believe that the earth was flat, and was skeptical of any "pagan" knowledge.

Well, IMO, that pagan "knowledge" is alive and well nowadays, in the form of some aspects of modern science regarding the earth.

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Like I said, the Church never taught the shape of the earth. Your quotes say nothing about the Church teaching regarding the shape of the earth. There never has been and there never will be any such teaching.
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Hi Neil,
Like you, I totally rejected flat earth as crazy talk. It was not until I began researching what the Church Fathers and the Bible have to say that I reluctantly changed my mind. This is from Flat Earth Trads. What do you think about geocentricism?
This is one of the most explicit quotation by the Church Fathers on the flat earth.

*Chap. XXIV.---Of the Antipodes, the Heaven, and the Stars.*

How is it with those who imagine that there are antipodes opposite to
our footsteps? Do they say anything to the purpose? Or is there any one
so senseless as to believe that there are men whose footsteps are higher
than their heads? or that the things which with us are in a recuмbent
position, with them hang in an inverted direction? that the crops and
trees grow downwards? that the rains, and snow, and hail fall upwards to
the earth? And does any one wonder that hanging gardens are mentioned
among the seven wonders of the world, when philosophers make hanging
fields, and seas, and cities, and mountains? The origin of this error
must also be set forth by us. For they are always deceived in the same
manner. For when they have assumed anything false in the commencement of
their investigations, led by the resemblance of the truth, they
necessarily fall into those things which are its consequences. Thus they
fall into many ridiculous things; because those things which are in
agreement with false things, must themselves be false. But since they
placed confidence in the first, they do not consider the character of
those things which follow, but defend them in every way; whereas they
ought to judge from those which follow, whether the first are true or false.

What course of argument, therefore, led them to the idea of the
antipodes? They saw the courses of the stars travelling towards the
west; they saw that the sun and the moon always set towards the same
quarter, and rise from the same. But since they did not perceive what
contrivance regulated their courses, nor how they returned from the west
to the east, but supposed that the heaven itself sloped downwards in
every direction, which appearance it must present on account of its
immense breadth, they thought that the world is round like a ball, and
they fancied that the heaven revolves in accordance with the motion of
the heavenly bodies; and thus that the stars and sun, when they have
set, by the very rapidity of the motion of the world are borne back to
the east. Therefore they both constructed brazen orbs, as though after
the figure of the world, and engraved upon them certain monstrous
images, which they said were constellations. It followed, therefore,
from this rotundity of the heaven, that the earth was enclosed in the
midst of its curved surface. But if this were so, the earth also itself
must be like a globe; for that could not possibly be anything but round,
which was held enclosed by that which was round. But if the earth also
were round, it must necessarily happen that it should present the same
appearance to all parts of the heaven; that is, that it should raise
aloft mountains, extend plains, and have level seas. And if this were
so, that last consequence also followed, that there would be no part of
the earth uninhabited by men and the other animals. Thus the rotundity
of the earth leads, in addition, to the invention of those suspended
antipodes.

But if you inquire from those who defend these marvellous fictions, why
all things do not fall into that lower part of the heaven, they reply
that such is the nature of things, that heavy bodies are borne to the
middle, and that they are all joined together towards the middle, as we
see spokes in a wheel; but that the bodies which are light, as mist,
smoke, and fire, are borne away from the middle, so as to seek the
heaven. I am at a loss what to say respecting those who, when they have
once erred, consistently persevere in their folly, and defend one vain
thing by another; but that I sometimes imagine that they either discuss
philosophy for the sake of a jest, or purposely and knowingly undertake
to defend falsehoods, as if to exercise or display their talents on
false subjects. But I should be able to prove by many arguments that it
is impossible for the heaven to be lower than the earth, were is not
that this book must now be concluded, and that some things still remain,
which are more necessary for the present work. And since it is not the
work of a single book to run over the errors of each individually, let
it be sufficient to have enumerated a few, from which the nature of the
others may be understood.
http://flatearthtrads.forumga.net/t59-lactentius-on-the-flat-earth-explicit

Just a point of curiosity. Earth aside, are the planets or moon a flat shape....or the sun flat for that matter?  Not looking to argue, but was curious.  I've seen a few of the other planets years ago when I was a teen using a relative's very expensive telescopes.  If earth is flat with the sun rotating above, what makes the planets and moon lay in the position they do, observable by earth?  Wouldn't they appear disk shaped as well or at least one of them appear in a flat plate like position  If gravity isn't a real thing, then what keeps the rest of planets moving on a tract that we can monitor and predict?

There are no planets per se.  All are stars, except the sun and moon.  A handful are called wandering stars because they do not follow the usual orbit but change course.  Consider Jupiter now retrograding in Virgo for 9 months before exiting on its way.  This short video proves stars are not terra firma 'worlds' people think are globular, but are provably flashing lights.  I personally have verified many stars on my own P900 camera (83x zoom) and while this video is a little more in focus than mine (better tripod), the star shown is exactly as depicted here.
https://m.youtube.com/watch?v=vymd3wgaBL0