The speaker addresses someone absent or dead, a thing, a place or an idea, as if they could hear.
In Paradise
be, Christians, more serious as you move; do not be like a feather in every wind, nor believe that every water washes you
Beatrice addresses all the "Christians", who are not before her, and gives them an order in the tone of counsel. The vocative changes the audience of the canto: the lesson on the vow stops being a conversation with Dante and comes to apply to whoever reads.
Cantos V to VIII: Mercury and Venus, Beatrice, at the end of the lesson on the vow
now stay, reader, on your bench, ruminating on what has only been tasted, if you wish to be glad long before you grow weary
Cantos IX to XII: Venus and the Sun, Dante, narrator, on entering the heaven of the Sun
O my frond, in whom I took pleasure only in waiting, I was your root: such a beginning, answering, made me
Cantos XIII to XVI: The Sun and Mars, Cacciaguida, to Dante, responding to the request for his name
they cover their palfreys with their cloaks, so that two beasts go under one skin: O patience, you who bear so much!
in shepherd's garb, ravening wolves can be seen from up here in every pasture: O defense of God, why do you still lie? With our blood, Cahorsines and Gascons prepare to drink: O good beginning, to what vile end you must fall!
lady, you are so great and so worthy that whoever seeks grace and does not turn to you wants his desire to fly without wings
Cantos XXIX to XXXIII: The Empyrean, Saint Bernard, in the prayer to the Virgin
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