Nitpick: The historical problem with stars being suns wasn't (just) the universe being larger than the solar system, but that the telescopic observations available at the time seemed to imply that every other visible star would have to be much larger than the Sun, in fact larger than the orbit of Saturn. This was because early astronomers didn't understand optical diffraction and thought the Airy disks visible around stars were the stars themselves, making their angular radius in Earth's sky seem vastly larger than the reality. [1] Both characterization of the Airy disk and observation of stellar parallax didn't occur until the 19th century, by which point religious objections wouldn't have had the same status as in Galileo's day anyway (for example, Darwin's work was published only a few decades later).

Source: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.612...