Here we find the moat of thieves. And just as a lizard, with a quick, slick slither, Flicks across the highway from hedge to hedge, Fleeter than a flash, in the battering dog-day weather, A fiery little monster, livid, in a rage, Black as any peppercorn, came and made a dart At the guts of the others, and leaping to engage One of the pair, it pierced him at the part Through which we first draw food; then loosed its grip And fell before him, outstretched and apart.

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..."

Will cannot be quenched against its will.

Astrology, the noblest of sciences.

Because your question searches for deep meaning, I shall explain in simple words

He loves but little who can say and count in words, how much he loves.

Through me you go into a city of weeping; through me you go into eternal pain; through me you go amongst the lost people