The following summary of Paradiso is very brief. However, you may access more elaborate treatments of different phases of Dante’s journey through the heavens by using the appropriate links.
The Roman poet Virgil had guided Dante through the sinister regions of hell. Then they had climbed the slopes of Mount Purgatory. At its summit, Dante had encountered Beatrice, who was to serve as his guide as he visited the ten heavens of the celestial realm.
Dante and Beatrice did not need any space suits or rockets. Since they were drawn upward toward God, they rose heavenward without the help of any vehicle. They traveled faster than lightning.
The Sphere of the Moon
They first visited the sphere of the moon. In this heavenly realm, Dante conversed with the spirit of Piccarda Donati. She had become a nun, but her brother Corso Donati had removed her from her convent and forced her to marry. He also saw other spirits who had been forced to break their vows of celibacy, such as Constance, who had become the wife of Henry VI, an emperor of the Holy Roman Empire.
The Sphere of Mercury
After spending time on the moon, Dante and Beatrice ascended to the sphere of Mercury. Here he met the spirit of the Roman emperor Justinian, who spoke at length about the history of the Roman Empire and its sequel, the Holy Roman Empire.
The Sphere of Venus
Their next stop was the sphere of Venus, where he conversed with Charles Martel. This was not the famous Charles Martel whose descendants became Carolingian emperors, but a contemporary of Dante who died young.
In the same sphere, Dante also conversed with two other spirits: Cunizza da Romano, the sister of a notorious Italian prince named Ezzelino da Romano, and a poet named Folco, who had lived in Marseilles.
The Sphere of the Sun
Their fourth stop was the sphere of the sun. Here Dante encountered the spirits of various theologians, especially St. Thomas Aquinas and St. Bonaventure. The spirit of King Solomon was also present.
Although St. Thomas Aquinas was a Dominican, he eulogized St. Francis of Assisi, the founder of the rival Franciscan order. St. Bonaventure, a Franciscan, returned the compliment by eulogizing St. Dominic.
The spirits also explained other things about which Dante was puzzled. For example, St. Thomas Aquinas explained the nature of King Solomon’s wisdom and its limitations. God had given Solomon the wisdom he needed to rule well. He was the wisest of the kings, and was able to rule well. However, this did not mean that his wisdom was preeminent in other areas also. In particular, he probably would have had trouble trying to solve the problems with which scholastic theologians concerned themselves.
The Sphere of Mars
The fifth heaven was the sphere of Mars. Here Dante saw a huge cross on which spirits were moving from top to bottom and from side to side. One of these spirits was Dante’s ancestor Cacciaguida, who imparted some unpleasant personal information to Dante.
Florence was Dante’s home, but he was living in exile when he wrote The Divine Comedy. However, Dante’s epic journey was supposed to take place in the year 1300, which was before Dante suffered exile. Therefore, when Dante visited Mars, he did not know about his misfortune until Cacciaguida told Dante what would happen.
The Sphere of Jupiter
In the sixth heaven, the sphere of Jupiter, a large number of spirits organized themselves to form letters. They spelled out the message: “DILIGATE JUSTITIAM, QUI JUDICATIS TERRA,” which means; “Love justice, ye who judge the earth.”
Most of the spirits that appeared on the planet Jupiter had been monarchs, so they naturally concerned themselves with justice.
After spelling out this sentence, the spirits reorganized themselves to form an eagle. The eagle was the standard of ancient Rome, as well as the Holy Roman Empire.
In the lower spheres, individual spirits had conversed with Dante. Here all the spirits spoke with one voice through the mouth of the eagle. At Dante’s request, it offered a discourse on divine justice.
One of the spirits that Dante beheld in this marvelous eagle was the spirit of the Roman emperor Trajan. He had died as a heathen. However, as a result of a prayer of Pope Gregory I, Trajan had been raised from the dead. His new life did not last long, but Pope Gregory quickly converted him to Christianity before he died a second time.
The Sphere of Saturn
The seventh heaven was the sphere of Saturn. Here he saw a ladder that extended upward to the higher realms. A host of spirits used this ladder to descend to the sphere of Saturn. One of them was Peter Damian, who had been active in church reform. He approached Dante and welcomed him.
The spirits who appeared to Dante in the sphere of Saturn were contemplative spirits. Dante also spoke with Benedict of Nursia, the founder of the Benedictine order.
Some aspects of the Saturnian environment puzzled Dante. In the lower spheres, Dante always enjoyed the smiles of Beatrice, but here she kept a straight face. Moreover, in the lower spheres, he heard a lot of celestial music, but the sphere of Saturn was strangely silent. He learned that his own weakness was causing these phenomena. If Dante heard celestial music in the sphere of Saturn, he would be overwhelmed; and if Beatrice had smiled, he would have been reduced to ashes.
The Sphere of the Fixed Stars
In the eighth heaven, the sphere of the fixed stars, Christ briefly appeared to Dante as a brilliant light. Dante’s eyes were temporarily overwhelmed, but he received increased strength as a result. He could now see the smile of Beatrice without suffering harm.
He also saw Mary, the mother of Jesus, as well as the apostles Peter, James, and John.
Dante submitted to a theological examination. Peter examined Dante on the topic of faith. James examined him on hope. John examined him on love.
The Primum Mobile
The Primum Mobile was the outermost sphere of the created universe. It was just below the Empyrean.
The spheres that were closer to the earth moved more slowly than the spheres that were farther away. Therefore, the Primum Mobile was the fastest moving sphere.
Then nine orders of angels appeared to Dante in the Primum Mobile. They appeared as nine concentric circles moving about a point of light. The point of light represented God.
While the nine created spheres moved, the Empyrean was at rest. The Empyrean was the eternal home of God, the blessed angels, and the souls who enjoyed everlasting life. All the spirits that had appeared to Dante in the nine created celestial spheres really lived in the Empyrean.
In order to see all that the Empyrean had to offer, the eyes of Dante had to receive further strength, not only once, but on three different occasions.
He saw a Celestial Rose in which each blessed spirit was assigned a seat. Beatrice left Dante and returned to her seat, while Saint Bernard came to assist Dante as he completed his celestial experience. He pointed out some prominent spirits, such as Mary, John the Baptist, Adam, Eve, and Peter.
Dante’s final sight was a vision of the Holy Trinity. He viewed God’s unity, as well as the three persons in the Godhead. He also noticed the human nature of Christ.
“Paradiso” from “The Divine Comedy of Dante Alighieri”; Italian text with English translation by Allen Mandelbaum; Notes by Anthony Oldcorn, Daniel Feldman, and Giuseppe di Scipio