Acknowledging that communications media and modern transportation have brought the world's people "closer to one another than ever before," Pope Benedict lamented that true "understanding and communion" is "often superficial and difficult."

"Imbalances remain and not infrequently lead to conflict, (and) dialogue among generations is problematic," he said. "We daily witness events which seem to show that mankind is becoming more aggressive and quarrelsome; understanding one another seems too arduous an undertaking, and we prefer to remain within ourselves and focus on our own our interests. ... Men are nursing a sense of diffidence, suspicion and reciprocal fear, to the extent that they have even become a danger to one another."

The pope observed that these social pathologies come amid unprecedented advances in human knowledge.

"Thanks to scientific and technological progress, we have acquired the power to dominate the forces of nature, to manipulate the elements, to fabricate living beings, almost going so far as to fabricate human beings," he said. "In such a situation, praying to God seems outmoded and useless, because we ourselves can construct and achieve anything we want."

Pope Benedict likened these developments to the Old Testament story of the Tower of Babel, according to which men came to think themselves "strong enough to be able to construct on their own a path to heaven in order to open its doors and put themselves in God's place."

That ambition bred conflict not only with God but among men, he said, since it caused them to lose "the ability to agree, to understand each other and to work together."

According to the biblical account of Babel, God "confused the language of all the earth" and scattered the builders as punishment for their presumption.

Pope Benedict said the remedy for today's strife is the same one bestowed at the first Pentecost, when the "flame of the Holy Spirit descended on the gathered disciples ... and lit in them the divine fire, a fire of love with the power to transform."

Among the consequences then, the pope noted, was that the disciples "began to speak freely, such that all were able to understand the news of Jesus Christ dead and risen again."

"At Pentecost, where there was division and estrangement, there are born unity and understanding," he said.

The Holy Spirit "sustains and unites" mankind, the pope said, and also resolves interior conflicts within each person, between the constantly struggling impulses of the flesh and the spirit.

After the Mass, before praying the "Regina Coeli" at the window of his study overlooking St. Peter's Square, Pope Benedict announced that he will proclaim St. John of Avila, a 16th-century Spanish priest, and St. Hildegard of Bingen, a 12th-century German abbess, as doctors of the universal church Oct. 7 in Rome.

The doctors of the church, saints honored for particularly important contributions to theology and spirituality, come from both the Eastern and Western church traditions. The current list of 33 doctors include early church fathers such as Sts. Jerome, John Chrysostom and Augustine, as well as major theologians such as Sts. Thomas Aquinas, Bonaventure and John of the Cross. The last saint named a doctor of the church was St. Therese of Lisieux, who was honored by Pope John Paul II in 1997. St. Hildegard will become the fourth woman doctor of the church, joining Sts. Therese, Catherine of Siena and Teresa of Avila.