All the necessity for eating ended with the life of the larva.

In the same manner religion teaches that the soul represents the changed state of man.

In this life a man is only like a caterpillar; death changes him into a chrysalis, and out of the chrysalis issues the winged soul which does not have to trouble itself about such matters as eating and drinking.

By the word "reptile" in this verse, you must understand caterpillar.

Therefore the poet speaks of all our human work as manifold motions making little speed; you have seen how many motions a caterpillar must make in order to go even a little distance, and you must have noticed the manner in which it spoils the appearance of the plant upon which it feeds.