Pope John Paul II Tuesday urged more aggressive efforts to spread church teachings in the Third World and cautioned Roman Catholics against the belief that "one religion is as good as another."

To underline his concern that missionary zeal is on the wane, the pope delivered his recommendations in an encyclical, the eighth of his 12-year-old papacy. An encyclical, a letter addressed to Catholics worldwide, embodies the church's most authoritative statement on a subject.The document addresses the church's relationships with other creeds and philosophies at a time of considerable tensions between Christian and Islamic cultures in some parts of the world.

While encouraging dialogue with those of other beliefs, the pope said such efforts aren't enough.

"We cannot be content when we consider the millions of our brothers and sisters, who like us have been redeemed by the blood of Christ but who live in ignorance of the love of God," the pope wrote. He called for more "zeal to pass on to others the light and joy of the faith," especially in view of the coming of the third millenium of Christianity.

While saying that conversion was the aim of preaching, the pontiff stressed freedom of religion, a precept not respected by early missionaries in the Americas.

But John Paul warned Catholics not to fall into the belief that "one religion is as good as another."