[16: 14, Ismen speaks to the King]
Soggiunge appresso: - Hor cosa aggiungo a queste
Fatte da me, ch'a me non meno aggrada:
Quando fia il Sol nel gran Leone celeste,
Vibrerà Marte seco ardente spada,
Né potran più temprar l'arsure infeste
Aure o nembi di pioggia o di rugiada;
Ma 'l Cane insieme uscito, horrida fiamma
Spargerà, che la terra e 'l cielo infiamma.
He then says, "I will add to these things
Made by me, a not less pleasant one:
When the Sun is in the heavenly Lion,
Mars will wield a fiery sword, nor will
The obnoxious heat be tempered
By air, or by rainy or dewy clouds;
The Dog will just then spread frightful
Flames to burn both the earth and the sky."
The Italian verses reported above correspond to the final printed text in which Tasso, further reworking the manuscript, modified many minor details and completely changed the last two lines. The final version, rather than the manuscript as we usually do, has been chosen because its details are better finished.
Astrology, together with magic, was a 'great hit' in Renaissance culture. Astrology was officially condemned, even mocked at -- see the Catholic Catechism of the Council of Trent (published in 1566) -- but the Popes themselves resorted to it. Moreover, it was the most "ecumenical" subject across the whole Mediterranean civilizations as astrology books were written, read, and shared by both Christians and Muslims and Jews. Tasso well witnessed this ambivalence in judgment in his long poem Il Mondo Creato, that he wrote in the same years in which he was preparing Gerusalemme Conquistata.