That was indeed the solar system of Ptolemy, but by Galileo's time there was no solid consensus. Some people still remembered the heliocentric theory of Aristarchus; others were inclined to the "Tychonic" system in which the other planets revolved around the sun, but the sun went around the earth. (This was popularised by Tycho de Brahe, but had first been proposed by Hipparchus of Nicaea)
Even Cardinal Bellarmine - initially one of Galileo's covert supporters - was prepared to accept the heliocentric theory if it could be proven, and reflected that, in such a case, our understanding of the Bible would have to be revised.
Anyone who was a denier of this dogma was persecuted by the Inquisition as a heretic.
Yes, when the matter was brought to a head by Urban VIII - whom Galileo had gratuitously offended by a passage in his Dialogo sopra i due massimi sistemi del mondo - the issue was indeed sent to the Congregation of the Holy Office, which famously replied:
"[The heiocentric proposition is] Philosophically (i.e., scientifically) foolish and absurd, and is considered official heresy because it explicitly contradicts the meaning of Scripture in many places, in terms of the verbal significance of the words and in terms of the accepted interpretation and understanding of the Church Fathers and the Doctors of Theology."
Their second phrase is hard to fault, since Scripture and the Fathers do indeed say exactly that. But they give no reason for their first phrase so we have no idea why they should think heliocentrism "foolish and absurd", and moreover no hint of why scientific theories should be judged by their seeming foolishness rather than by the experimental evidence.
Indeed, two world views in collision.
The fundamental error of the Holy Office was to elevate a scientific theory to a theological doctrine. Bellarmine was fortunately much wiser.
People forget that scientists came up with the Ptolomaic system—not theologians. The Fathers merely accepted the prevailing scientific theory and, to some extent, built a theology around it (cf. Dante).
As to why the Holy Office thought it was scientifically foolish and absurd, I’m not sure. Maybe because if the earth moved then there had to be a stellar parallax, and no one had ever been able to see one. Course we know now there is a parallax—it’s just too small to see with the technology they had available.