Lines or verses set one after another with the same construction, so that the reader compares what changes from one to the next.
In Purgatory
We all died by force, and were sinners until the last hour; there a light from heaven made us aware, so that, repenting and forgiving, we left life at peace with God, who stirs in us the desire to see him.
The two gerunds "repenting and forgiving" repeat the same construction and set side by side the two acts that saved the crowd. The symmetry places the two acts, repenting and forgiving, side by side, with no order between them.
Cantos V to VIII: Those who repented late, The men who died by force, speaking together to Dante
the natural is always without error, but the other can err, through a bad object, or through too much or too little vigor.
Cantos XVII to XXI: Love, sloth and avarice, Virgil, to Dante, in the lesson on love
do not wait any longer for my word or my nod; free, upright and sound is your free will, and it would be an error not to act according to its desire: therefore I crown and mitre you over yourself.
Cantos XXVI to XXIX: The fire and Eden, Virgil, to Dante, in his last speech before falling silent
on this side it descends with the virtue of taking the memory of sin from someone; on the other, it gives back the memory of every good deed. From here, Lethe; so, on the other side, it is called Eunoe, and it does not work unless it has first been tasted on one side and on the other.
Cantos XXVI to XXIX: The fire and Eden, Matelda, to Dante, explaining the two waters of Eden
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