Theology
Although theology is important to all of Dante’s Commedia, nowhere is it more important than in the Paradiso. Beatrice’s aim in the canticle is to correct Dante’s intellect, and much of this intellectual change occurs through theological discussion. Indeed, the Paradiso involves far more dialogue than either the Inferno or the Purgatorio, and much of this dialogue is explicitly theological, arguing through the thorny problems of creation, divinity, and church practice. Thus, Dante’s theological focus is reflected in the very methods of the poem itself, as he turns more frequently to the sort of theological dialogue found in other medieval works (such as Boethius’s Consolation of Philosophy, for example).
Even on the structural level, theology plays a major role. One could argue that the climax of the poem begins with the Apostle’s examination of Dante’s faith. These examinations borrow the form of a medieval magisterial examination for theology; in other words, Dante crafts a scene as if he is, in his own poem, being questioned to see if he can obtain a degree in theology. He passes these examinations, of course, by showing his precise theological knowledge as well as his faith, and we as readers are made to understand the importance, for Dante, of this school of philosophical thinking.
Love and Desire
In the Purgatorio, Dante developed his concept of Divine Love, suggesting that all virtuous actions are inspired by it. In the Paradiso, Dante continues to develop the theme of love. Yet, in the Paradiso, Dante focuses more on the fulfillment of desire in Divine Love. As Benedict describes, all desires are fulfilled in God’s Paradise. Thus, many of the souls that interact with Dante discuss the effects of God’s love on them; Piccarda, the first soul Dante interacts with, even states that “the power of love subdues our will.” This focus on love is reflected in Dante and Beatrice’s relationship as well: as they ascend from sphere to sphere, Dante’s love for Beatrice grows as her beauty grows. As they near God, Dante’s love for Beatrice nears fulfillment. We might then consider that Dante’s spiritual and intellectual journey is also a journey towards the fulfillment of desire. Note that Beatrice describes God as “light intellectual, full of love,/love of true good, full of joy,/joy that surpasses every sweetness.” “Love,” repeated twice, is literally at the core of God’s "eternal Light," wedged firmly between the intellect and the experience of joy.
History and Politics
Although the politics of Dante's time may be a less marked presence in the Paradiso, Dante's politics remain an important theme, especially as Dante integrates historical figures among the saved. Figures like Justinian suggest his support of the Holy Roman Empire; Charles Martel, himself a nobleman, is praised. Martel also criticizes those corrupt politicians around him. Even Cacciaguida's speech has an explicitly political dimension: after he praises Florence of old, he turns to criticize the corrupt Florence of Dante's time. Similarly, the Apostle Peter (and many other figures in heaven) are critical of papal and Church corruption. These criticisms are not merely theological; because the Church was, in essence, the greatest political power in the Middle Ages, these criticisms are implicitly political. Still, throughout all of this criticism, Dante uses prophecies to look towards an Italian, imperial, and Catholic future in which problems of violence and corruption have been remedied by divine action.
Language
Perhaps the most ever-present theme of the Paradiso is, unexpectedly, the failure of language. Although it was something of a trope within classical poetry to suggest that you were unable to describe something, Dante turns this emphasis of the indescribable into a persistent and developed theme, integrating it into Christian notions of the fall. Frequently, Dante tells the reader forthright that he is unable to capture an image seen in heaven in language; these instances become more and more frequently as he becomes closer to God, until he admits total defeat. In his conversation with Adam, Dante might give us a clue as to why he is so insistent that language fail: after the Fall, original sin, and the Tower of Babel (where God separated human language into many separate languages), language is impoverished and ultimately mediates us from God, rather than giving one an unmediated vision. Thus, in the place of language, Dante praises vision, and it is on a vision of God that he ends the Commedia.
Guidance
Now that Virgil has returned to the underworld, Beatrice has taken his place, guiding Dante through the final third of his spiritual pilgrimage. But Beatrice is no poor substitute for Virgil, and her guidance—and guidance in general—remains as important to the themes of the Commedia as ever. As stated above, an important difference between Beatrice’s and Virgil’s guidance is that Beatrice is focused on correcting Dante’s intellect and not his will. Notice that, while Dante’s will was broken, he was limping and had difficulty traveling from place to place, becoming better able to walk and climb only at the end of the Purgatorio. Having received the guidance necessary for his will’s correction, Dante now travels easily. But it is now his vision that has trouble: it often fails in the face of Divine Light (and when looking at Beatrice’s face). Thus, like Dante’s limping foot, which represented his limping will, Dante’s failing vision represents the problems in his intellect. By the end of the Paradiso, though, the virtue of Mary and the assistance of God allow him to see heaven in all its splendor, suggesting that his intellectual guidance is completed.
Hope
The importance of hope to the Commedia is evident throughout, and in the Paradiso, Dante develops what it is and its importance to himself. While being questioned by the apostles, Beatrice makes sure to let them know that Dante is the most hopeful of all mortal Christians; soon after, he gives his definition of hope, which is that hope “is the certain expectation/of future glory, springing/from heavenly grace and merit we have won.” This definition of hope places emphasis on the certainty of this hope. This is not merely a desire for a Christian future but a certain belief, and this certain belief is reflected all throughout the Paradiso. As much as Dante’s characters are critical of his contemporaries, these characters often end their speeches with prophecies that suggest, as a certainty, that there is hope for the future.
Virtue
In the Inferno and the Purgatorio, sin and penitence were major themes, and they even gave structure to Hell and the Mountain of Purgatory, respectively. In the Paradiso, this sort of structure (where each section is accompanied by a corresponding sin and punishment) is present, although it is not quite as visible, as no stark punishments dramatize the sins of those around Dante. Still, Paradise is structured largely around virtue. The first three spheres of Paradise involve those who were not perfectly virtuous: these are the inconstant on the moon, the ambitious on Mercury, and those who were overly amorous on Venus. These souls did not fully have the virtue of fortitude, justice, and temperance, respectively. Yet, once Dante reaches the sun, we enter the territory of perfect (or near-perfect) virtue. The souls in the sun are especially wise and prudent. On Mars, Dante focuses on those military leaders who were especially strong in fortitude. On Jupiter, Dante focuses on those political leaders who were especially just. One Saturn, Dante focuses on temperance. Ultimately, this focus on virtue is completed when Dante sees Beatrice, in whom all virtues are joined.
