John examines Dante on the greatest of the theological virtues: love, charity. Who or what is the highest object of his love? Dante's answer is a philosophical and scriptural cascade: I love God because He is the Good beyond which nothing better can be imagined; because the truth of this is demonstrated by Aristotle, by Scripture, and by the authority of the Church's whole tradition; because the whole world bears the imprint of His love; and because the human mind, by its very nature, desires above all the good that is its cause and end. John is satisfied. The blessed sing to Dante — "Sanctus, Sanctus, Sanctus" — and his sight is restored by Beatrice's gaze, sharper than before.
Among the blazing souls, one steps forward — ancient, singular, lit with a quiet, profound joy. It is Adam, the first man, father of the human race. Dante is overcome. Adam, reading Dante's unspoken questions, answers four of them in sequence: how long ago did he live? He was in Eden for little more than six hours before the Fall; he was in Limbo until Christ's Harrowing — 4302 years, which gives Dante a date for Adam's creation. What language did he speak? Not Hebrew, as medieval tradition held — the language Adam spoke died out long before Babel; all human languages change and die, like the leaves of a forest. The name he used for God was not El (Hebrew) but I — a simple sound. And the true cause of his exile from Eden? Not the eating of the fruit in itself, but the transgression of the boundary he had freely accepted — the presumption of crossing what God had bounded.