VATICAN CITY, APRIL 5, 2004 (Zenit.org).- John Paul II warned university students about the need to discern the "pitfalls" that advertising sometimes promotes, and encouraged them to use the possibilities it offers to communicate positive messages.

The Holy Father expressed these thoughts today to some 3,000 participants of the UNIV 2004 international congress, who came to Paul VI Hall for a papal audience.

Commenting on the theme "Project Culture: The Language of Advertising," which brought the university students together, John Paul II stressed that it "is necessary to know how to use the appropriate language to transmit positive messages, and to make noble ideals and initiatives known in an attractive way."

At the same time, the Pope added, "it is imperative to discern the limits and pitfalls of the languages proposed to us by the media."

"At times, advertisements offer a superficial and inadequate view of life, of the person, of the family, and of morality," he said in his address, delivered in Italian.

In this task of promotion of lofty values and discernment, the Pope said that Christians must "follow Jesus closely, with the help of prayer and contemplation."

"Moreover, to be his friends in the world in which we live calls for an effort to go against the current," he added, repeating an expression he used during his homily on Palm Sunday.

"May you not be afraid in the university, the school, and the places where you meet, to be anti-conformists when necessary," the Pope told his young listeners.

The Holy Father invited them to spread the Christian view of the virtue of purity, to show their contemporaries that the virtue "is born of love."

"May the desire in the depth of your hearts to see Jesus never be extinguished!" he exclaimed. "Learn to overcome superficial emotions, resisting the seduction of pleasures and the ambitions of egoism and comfort."

"To improve the world, make every effort above all to change yourselves through recourse to the sacrament of penance and profound identification with Christ in the Eucharist," the Pontiff recommended before concluding.

With the help of Opus Dei, the UNIV university congress has been held annually in Rome during Holy Week since 1968. It is organized by the Institute for University Cooperation, an Italian group that promotes initiatives of cooperation for development in many countries.

In his address to Justin Gillespie, president of the university congress, John Paul II said that "like millions of other Catholics from this country, I have felt a special need to unite myself to your constant prayer for peace."

"I thank you for constantly reminding us that we seek a peace that is unique; a peace that cannot result from the decrees of enlightened men, or the slogans of marching masses," the Holy Father added.

"The only peace that can truly triumph over the horrors that with ever greater speed seem to multiply the world over is that peace which Christ promised: 'Peace be with you, my peace I give you; not as the world gives peace do I give peace to you,'" the Pope said.

The president of the congress replied: "During this week, Holy Father, we want to commit ourselves more completely to Christ, so that through our daily lives, he might personally bring this peace to thousands of men and women all over the world."