Sarpi

Venice was a particular thorn in his flesh, not least because Paolo Sarpi, by now a theological adviser to the Doge, openly argued that the road to Heaven lay through spiritual works alone and denied the so-called ‘divine right’ of kings and popes to exercise political power in the name of God.

The attempt on Sarpi’s life made a deep impression on Galileo, who realized that even if the Venetian Republic could stand up to Rome, individuals who failed to toe the Catholic line would be at risk anywhere in Italy.

Although Sarpi may have been slow to realize its importance, Galileo immediately realized that an instrument that could make distant objects visible would be of enormous military and trade importance to Venice, where fortunes often depended on being first to identify which ships were approaching the port.

Sarpi was so unorthodox a Catholic that some of his opponents would later suspect him of being a closet Protestant, while Bellarmine was a leading establishment figure, a theologian and intellectual who would play a major part in the prosecution of Giordano Bruno for heresy.

The result was that in 1606, the Pope excommunicated the Doge of Venice and all his officials, including Sarpi.