In the geocentric model of the solar system, as Venus moves on its epicycle (while the epicycle moves around the Earth), it is always in between the Earth and the Sun.  Therefore, the only possible phases of Venus would be new and crescent phases.
<a href="//commons.wikimedia.org/w/index.php?title=User:Astrobryguy&amp;action=edit&amp;redlink=1" class="new" title="User:Astrobryguy (page does not exist)">Astrobryguy</a> Derivative work of <a href="https://en.wikipedia.org/wiki/File:Phases-of-Venus2.svg" class="extiw" title="en:File:Phases-of-Venus2.svg">en:File:Phases-of-Venus2.svg</a> (released to public domain).
2011-09-25
<span class="int-own-work" lang="en">Own work</span>