Like the lark that soars in the air, first singing, then silent, content with the last sweetness that satiates it, such seemed to me that image, the imprint of the Eternal Pleasure.
And here Dante describes an evidently spherical world... "The lamp of the world [the sun] rises to mortals through different passages; but through that which joins four circles with three crosses [the position of the rising sun at the vernal equinox] it issues with a better course and conjoined with better stars, and tempers and stamps the wax of the world more after its own fashion. Although such an outlet had made morning there and evening here, and all the hemisphere there was bright, and the other dark..."
Be like a solid tower whose brave height remains unmoved by all the winds that blow; the man who lets his thoughts be turned aside by one thing or another, will lose sight of his true goal, his mind sapped of its strength.