Antithesis

Placing opposite ideas or words side by side, so that one lights up the other through contrast.

In Purgatory

my sins were horrible; but infinite goodness has arms so great that it takes in everything that turns to it.

The "horrible sins" stand on one side and the "infinite goodness" on the other, linked by "but." The contrast in size organizes the sentence and shows that the greatness of forgiveness is measured by the gravity of what is forgiven.

Cantos I to IV: The shore and Ante-Purgatory, Manfred, to Dante, recounting how he surrendered before he died

not by doing, but by not doing, I lost the power to see the high Sun that you desire, and that was known to me too late.

Cantos V to VIII: Those who repented late, Virgil, to Sordello, explaining why he lost heaven

I have them from Peter; and he told me that I should err more in opening than in keeping closed, provided people prostrate themselves at my feet. Then he pushed the leaf of the sacred door, saying: enter; but I warn you that whoever looks back goes back outside.

Cantos IX to XII: The gate and pride, the gatekeeping angel, to Dante and Virgil, opening the gate of Purgatory

and I saw him bend toward the earth under the death that already weighed on him, but with his eyes he always made doors toward heaven, praying to the high Lord, amid so much war, that he forgive his persecutors, with that look that opens pity.

Cantos XIII to XVI: Envy and wrath, Dante, narrator, describing the third vision of meekness

nature 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

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

here you will be a forest dweller for a short time, and you will be with me, without end, a citizen of that Rome of which Christ is Roman. For this reason, for the good of a world that lives badly, keep your eyes now on the chariot, and what you see, when you return there, make sure you write it down.

Cantos XXX to XXXIII: Beatrice, Beatrice, to Dante, seated at the root of the new tree