Your fame is as the grass, whose hue comes and goes, and His might withers it by whose power it sprang from the lap of the earth.

Midway along the journey of our life I woke to find myself in a dark wood, for I had wandered off from the straight path. How hard it is to tell what it was like, this wood of wilderness, savage and stubborn (the thought of it brings back all my old fears), a bitter place! Death could scarce be bitterer. But if I would show the good that came of it I must talk about things other than the good.

I found myself within a forest dark, for the straightfoward pathway had been lost. Ah me! How hard a thing is to say, what was this forest savage, rough, and stern, which in the very thought renews the fear. So bitter is it, death is little more.

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

The wisest are the most annoyed at the loss of time.

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..."

There is no greater pain than to remember, in our present grief, past happiness.