It is clearly we, I say, who make rough the straight and smooth paths of the Lord with the wicked and hard rocks of our desires, who very foolishly abandon the royal road paved with apostolic and prophetic stones and made level by the footsteps of all the holy ones and of the Lord himself, and who pursue byways and brambly roads. Blinded by the seductions of present pleasures, we crawl along the dark and obstructed trails, our feet lacerated by the thorns of vice and our wedding garment in tatters, and we are not only pierced by the sharp needles of thorny bushes but also brought low by the stings of the poisonous serpents and the scorpions that lie in wait there. .
It is plain, I say, that it is we, who make rough with the nasty and hard stones of our desires the right and smooth paths of the Lord; who most foolishly forsake the royal road paved with the fine pebbles of apostles and prophets, and trodden down by the footsteps of all the saints and of the Lord himself, and seek trackless and thorny places. Blinded by the allurements of present delights, we make our way with wounded feet and our wedding garment rent, through dark paths, overrun with the briars of sins, so as not only to be pierced by the sharp thorns of the brambles but actually laid low by the bites of deadly serpents and scorpions lurking there.
To walk in the good way, etc. The good way, he calls the unity of true faith, about which the Lord says, I am the way (John XIV); and again: No one can come to the Father, except through me (Ibid.). But the paths of the righteous, he names the various examples of the saints. This verse depends on what was said above: Prudence will preserve you; as also that, To be delivered from the strange woman.
[AD 435] John Cassian on Proverbs 2:20