During his almost eight-year pontificate, Pope Benedict XVI impressed the world as a teacher, guiding Catholics to the sources of the faith and urging modern society not to turn its back on God.Citing his age and diminishing energy, the 85-year-old pope announced Feb. 11 that he would be resigning effective Feb. 28 and would devote the rest of his life to prayer.As pastor of the universal church, he used virtually every medium at his disposal — books and Twitter, sermons and encyclicals — to catechize the faithful on the foundational beliefs and practices of Christianity, ranging from the sermons of St. Augustine to the sign of the cross.Having served in his 30s as an influential adviser during the 1962-65 Second Vatican Council, he made it a priority as pope to correct what he saw as overly expansive interpretations of Vatican II in favor of readings that stressed the council's continuity with the church's millennial traditions.Under his oversight, the Vatican continued to highlight the church's moral boundaries on issues such as end-of-life medical care, marriage and homosexuality. But the pope's message to society at large focused less on single issues and more on the risk of losing the basic relationship between the human being and the Creator.He consistently warned the West that unless its secularized society rediscovered religious values, it could not hope to engage in real dialogue with Islamic and other religious cultures.In his encyclicals and in his books on "Jesus of Nazareth," the pope honed that message, asking readers to discover the essential connections between sacrificial love, works of charity, a dedication to the truth and the Gospel of Christ.The German-born pontiff did not try to match the popularity of his predecessor, Pope John Paul II, but the millions of people who came to see him in Rome and abroad came to appreciate his smile, his frequent ad libs and his ability to speak from the heart.Although he did not expect to travel much, he ended up making 24 trips to six continents and three times presided over World Youth Day mega-gatherings, in Germany in 2005, in Australia in 2008, and in Spain in 2011.Talking about aging last March when he met the 85-year-old Cuban leader Fidel Castro in Havana, Pope Benedict told him, "Yes, I'm old, but I can still carry out my duties."On a historic visit to the United States in 2008, the pope brought his own identity into clearer focus for Americans. He set forth a moral challenge on issues ranging from economic justice to abortion. He also took church recognition of the priestly sex abuse scandal to a new level, expressing his personal shame at what happened and praying with the victims.The pope met three times with former U.S. President George W. Bush, including a formal visit to the White House, and the two leaders found wide areas of agreement on pro-life and family issues. When President Barack Obama was elected, the pontiff sent him a warmly worded telegram and a promise of his prayers, but when they met at the Vatican the next year, the pope spoke clearly about the church's objections to the administration's policies on several life issues, including abortion and embryonic stem cell research.Pope Benedict was 78 and in apparent good health when elected April 19, 2005, but was said to have told his fellow cardinals that his would not be a long papacy like that of his predecessor. In an interview with the German author Peter Seewald in 2010, Pope Benedict said: "If a pope clearly realizes that he is no longer physically, psychologically and spiritually capable of handling the duties of his office, then he has a right and, under some circumstances, also an obligation to resign."As inevitable as his election seemed after Blessed John Paul died in 2005, his path to the papacy was long and indirect.Joseph Ratzinger was born April 16, 1927, in the Bavarian town of Marktl am Inn, the third and youngest child of a police officer, Joseph Sr., and his wife, Maria. Young Joseph joined his brother, Georg, at a minor seminary in 1939.Like other young students, he was automatically enrolled in the Hitler Youth program, but soon stopped going to meetings. During World War II, he was conscripted into the army, and in the spring of 1945 he deserted his unit and returned home, spending a few months in an Allied prisoner-of-war camp. He returned to the seminary late in 1945 and was ordained six years later, along with his brother.In a meeting with young people in 2006, the pope said witnessing the brutality of the Nazi regime helped convince him to become a priest. But he also had to overcome some doubts, he said. For one thing, he asked himself whether he "could faithfully live celibacy" his entire life. He also recognized that his real leanings were toward theology and wondered whether he had the qualities of a good pastor and the ability "to be simple with the simple people."After a short stint as a parish priest, the future pope began a teaching career and built a reputation as one of the church's foremost theologians. At Vatican II, he made important contributions as a theological expert and embraced the council's early work. But he began to have misgivings about an emerging anti-Roman bias, the idea of a "church from below" run on a parliamentary model, and the direction of theological research in the church — criticism that would become even sharper in later years.In a 2005 speech that served as a kind of manifesto for his young papacy, Pope Benedict rejected what he called a "hermeneutic of discontinuity and rupture" in interpreting Vatican II as a radical break with the past. The pope called instead for reading the council through a "hermeneutic of reform" in continuity with Catholic tradition.In 1977, Pope Paul VI named him archbishop of Munich and Freising, and four years later Pope John Paul called him to head the Congregation for the Doctrine of the Faith, where he wielded great influence on issues such as liberation theology, dissent from church teachings and pressure for women's ordination. Serving in this role for nearly a quarter century, then-Cardinal Ratzinger earned a reputation in some quarters as a sort of grand inquisitor, seeking to stamp out independent thinking, an image belied by his passion for debate with thinkers inside and outside the church.As the newly elected pope in 2005, he explained that he took the name Benedict to evoke the memory of Pope Benedict XV, a "courageous prophet of peace" during World War I, and said he wanted to place his ministry at the service of reconciliation and harmony among peoples.The new pope spent most of his energy writing and preaching, in encyclicals, letters, messages, homilies and talks that eventually numbered more than a thousand.Surprising those who had expected a by-the-book pontificate from a man who had spent more than 23 years as the Vatican's chief doctrinal official, Pope Benedict emphasized that Christianity was a religion of love and not a religion of rules.During the 2010-11 Year for Priests, Pope Benedict held up the 19th-century French St. John Vianney as a model of clerical holiness who struggled against the indifference and hostility of a militantly secular society.He convened a Synod of Bishops on Scripture in 2008, in an effort to move the Bible back to the center of individual spirituality and pastoral planning. He opened a Year of Faith in October presided over a synod focusing on the new evangelization and a revival of Christian faith in the secular West, one of the priorities of his pontificate.Some of Pope Benedict's most memorable statements came when he applied simple Gospel values to social issues such as the protection of human life, the environment and economics.When the global financial crisis worsened in 2008, for example, the pope insisted that financial institutions must put people before profits. He also reminded people that modern ideals of money and material success are passing realities, saying: "Whoever builds his life on these things — on material things, on success, on appearances — is building on sand."Pope Benedict's outreach to traditionalist Catholics brought him some opposition and criticism. In 2007, he widened the possible use of the Tridentine Mass and began introducing touches of antiquity in his own liturgies, including the requirement of kneeling when receiving Communion from the pope.Then in 2009, in an effort to reconcile with the traditionalist Society of St. Pius X, he lifted the excommunications of four of the society's bishops who were ordained illicitly in 1988.A storm of criticism erupted because one of the four, Bishop Richard Williamson, had made a number of statements — widely available on the Internet, but unknown to the pope — denying the extent of the Holocaust. The Vatican scrambled to distance Pope Benedict from the bishop's views and reaffirm the pontiff's commitment to Catholic-Jewish dialogue.The pope himself wrote an unusually personal letter to the world's bishops, defending his efforts to restore church unity by reaching out to traditionalists and expressing sadness that even some Catholics seemed ready to attack him "with open hostility."At the same time, he clearly acknowledged mistakes in Vatican communications and said the Holy See would have to do a better job using the Internet in the future. Instead, the mishaps continued, and for most of the year preceding Pope Benedict's resignation, press coverage of the Vatican was dominated by the so-called "VatiLeaks" affair, a scandal over confidential and sometimes embarrassing confidential documents that had been provided to the press, allegedly by the pope's own butler, Paolo Gabriele.A Vatican court found Gabriele guilty in October and sentenced him to 18 months in jail. Pope Benedict, meeting his former aide outside his cell in the Vatican police barracks, pardoned him just before Christmas.The pope's 2009 letter to bishops also summarized what he saw as his main mission as the successor of Peter: "In our days, when in vast areas of the world the faith is in danger of dying out like a flame which no longer has fuel, the overriding priority is to make God present in this world and to show men and women the way to God."The idea that God is disappearing from the human horizon and that humanity is losing its bearings with "evident destructive effects" was a theme Pope Benedict saw as common ground for dialogue between Christians and Muslims. He voiced the church's opposition to a potential "clash of civilizations" in which religion was seen as a defining difference. But sometimes his words drew as much criticism as praise, particularly among Muslims who felt the pope was unfairly questioning the foundations of their religion.In a lecture at Germany's University of Regensburg in 2006, the pope quoted a Christian medieval emperor who said the prophet Mohammed had brought "things only evil and inhuman, such as his command to spread by the sword the faith he preached." Following protests in the Islamic world, which included the burning of churches in the Palestinian territories and the murder of a nun in Somalia, the pope said he was sorry his words had offended Muslims and distanced himself from the text he had quoted.Later that year, visiting a mosque in Turkey, he turned toward Mecca and prayed silently alongside his host. This interfaith gesture generated considerable good will, and over the succeeding years, Pope Benedict continued to meet with Muslim leaders. Yet some Muslims continued to view the pope with suspicion or hostility, such as the prominent cleric who reiterated complaints about the Regensburg speech in the run-up to the pope's trip to Lebanon in September.Pope Benedict also visited synagogues, in Germany in 2005, in New York in 2008 and in Rome in 2010, and his strong condemnations of anti-Semitism won the appreciation of many Jewish leaders. However, tensions arose in 2008 over the wording of a prayer for Jewish conversion, which the pope had revised for use in the Tridentine-rite Good Friday liturgy.The pope considered Christian unity one of his priorities, and he took steps to improve dialogue with Orthodox churches in particular. The most visible sign was the pope's decision to accept the invitation of Ecumenical Patriarch Bartholomew of Constantinople to visit the patriarch at his headquarters in Istanbul, Turkey, in 2006. Two years later, the pope invited the patriarch to give a major address at the Synod of Bishops. The Vatican also arranged the resumption of theological talks with the Orthodox in mid-2006 and began new forms of cultural collaboration with the Russian Orthodox Church.The fate of Christian minorities around the world was one of the pope's major concerns, especially in places like Iraq and other predominantly Muslim countries. The pope strongly defended the right to religious freedom in his speech to the United Nations in 2008.In early 2007, the pope turned his attention to China, convening a meeting of church experts to discuss ways to bring unity to the church and gain concessions from the communist government. A papal letter to Chinese Catholics a few months later encouraged bold new steps to bridge the gap between Catholics registered with the government-controlled Catholic Patriotic Association and the so-called underground communities, whose leaders were frequently harassed or imprisoned by the authorities.The pope's letter also issued a broad invitation to government authorities for dialogue on the appointment of bishops and other topics. A number of bishops were subsequently ordained with both papal and government approval, before the government returned to the practice of choosing bishops without the Vatican's approval.One of the most important documents issued under Pope Benedict, and with his explicit approval, was a doctrinal congregation instruction on bioethics in 2008. The document warned that some developments in stem-cell research, gene therapy and embryonic experimentation violate moral principles and reflect an attempt by man to "take the place of his Creator."The pope's own writings frequently explored the relationship between personal faith in Christ and social consequences.His first encyclical, "Deus Caritas Est" ("God Is Love,"), issued in 2005, reminded all people that God loves them and called on them to share that love in a personal and social way. It won high praise, even from quarters typically critical of the church.Two years later, his second encyclical, "Spe Salvi" (on Christian hope), warned that without faith in God, humanity lies at the mercy of ideologies that can lead to "the greatest forms of cruelty and violations of justice."His third encyclical, "Caritas in Veritate" ("Charity in Truth") was released in 2009 and said ethical values are needed to overcome the current global economic crisis as well as to eradicate hunger and promote the real development of all the world's peoples.Several months ago, the Vatican said Pope Benedict had completed work on another encyclical, this one on the virtue of faith, and its publication was expected in the first half of this year. The Vatican has not said whether or not the letter would come out before the pope's resignation takes effect Feb. 28.His three-volume work, "Jesus of Nazareth," published between 2007 and 2012 in several languages, emphasized that Christ must be understood as the Son of God on a divine mission, not as a mere moralist or social reformer. The books argued that while Christ did not bring a blueprint for social progress, he did bring a new vision based on love that challenges the evils of today's world — from the brutality of totalitarian regimes to the "cruelty of capitalism."The pope spent much of his time meeting with bishops from around the world when they made "ad limina" visits to the Vatican to report on their dioceses.Some of Pope Benedict's longest and most-revealing encounters were with priests, in Rome and elsewhere. He frequently spoke of the importance of the quality formation of priestly candidates, and in 2005 he approved the release of a long-awaited document barring those with deep-seated homosexual tendencies from the priesthood.In a few areas, Pope Benedict asked church experts to engage in careful study and reflection:— He asked Vatican agencies to consider the moral and scientific aspects of condom use in AIDS prevention, after some theologians argued that condoms were acceptable for married couples in which one spouse is infected with HIV. At the same time, his own statement in 2009 that condom-distribution campaigns aggravate the problem of AIDS prompted widespread criticism.— He convened scientific and theological scholars for private discussions about the theory of evolution. In his own remarks on the subject, he emphasized that the acceptance of evolutionary theory should not mean the exclusion of a fundamental divine purpose in creation.One of the pope's most notable actions came in May 2006, when he approved a decision saying that Father Marcial Maciel Degollado, the founder of the Legionaries of Christ, should not exercise his priestly ministry publicly. Father Maciel, who enjoyed favor for many years at the Vatican, had been accused of sexually abusing minors. In 2009 the pope approved an apostolic visitation of the late priest's order.Although he was expected to reverse a trend set by Pope John Paul, Pope Benedict did not slow the Vatican's saint-making machinery, but he did immediately announce he would not preside over beatifications. The pope's decision was meant to highlight the difference between a beatification and a canonization, but, in effect, the pope's decision lowered the profile of beatification liturgies. Pope Benedict did make two exceptions to his new rule: the first to beatify Cardinal John Henry Newman during a September 2010 visit to England; and the second to beatify Pope John Paul in May 2011.While Pope Benedict asked Vatican experts to be more selective in picking candidates for sainthood, he ended up canonizing 44 new saints, including the Native American Kateri Tekakwitha and Mother Marianne Cope of Molokai.Pope Benedict named 90 new cardinals; 67 of those he named are still under the age of 80 and therefore eligible to vote in the conclave to elect his successor. As of Feb. 28, the day his papacy ends, Pope Benedict's appointments will represent just over 57 percent of the 117 cardinals under 80 that day.In mid-2007, the pope made an important change in the conclave procedure, restoring the traditional rule that requires a two-thirds majority for papal election. In doing so, he reversed a modification made by Pope John Paul, who had allowed the possibility of moving to a simple majority vote in the case of a deadlocked conclave.—CNSJohn Thavis, Francis X. Rocca and Cindy Wooden contributed to this story.{gallery width=100 height=100}gallery/2013/0215/bio/{/gallery}