Boston — Italy's Protestant Waldensians may be only .05 percent of the population - but they are still ''the conscience of the nation.'' The latter phrase was the spontaneous description given to Waldensian Pastor Giorgio Bouchard recently by the Socialist mayor of Milan.
The Waldensian conscience, back in the group's beginnings in the 12th century , involved making the Bible available in the vernacular, renouncing worldly possessions, and respecting the teaching gift of any lay person (and not just ordained clergy).
Today the denomination's conscience also includes social work, solidarity with third-world peoples, lobbying for peace, and demonstrating, in Mr. Bouchard's words, that ''Italy is becoming a pluralist country.''
Mr. Bouchard is currently on a three-week tour of the United States, explaining the unique role of the 30,000 Italian Waldensians in a country that is 85 percent Roman Catholic, 14 percent nonreligious, and only 1 percent Protestant, Jewish, Orthodox, and Muslim combined. He is visiting primarily seminaries and church groups.
A measure of the Waldensians' significance in Italy came earlier this year. The Waldensians - represented by Bouchard as the church's moderator, or chief administrative officer - became the first Protestant religion to sign an understanding, or intesa, with the Italian government following the new Concordat between the government and the Vatican.
Under the Concordat of Feb. 19, which is currently awaiting ratification, Roman Catholicism is no longer the state religion as it has been ever since the Mussolini Concordat of 1929. The church retains special privileges; the state will still pay for parish priests, army chaplains, the 20,000 teachers of religion in the public schools, and church building. But the Roman Catholic Church will no longer carry authority as the official state church.
In the Feb. 21 intesa, the Italian state recognizes further the independence of the recently united Waldensians and Methodists. This first intesa, Bouchard said, paves the way for agreements with other confessions, including the Jewish faith.
The state will not pay for Wal-densian activities - nor would the fiercely independent Waldensians accept state payment. But the state now recognizes the Waldensians' right to give pastoral care in prisons, hospitals, army barracks, and homes for the aged.
The state also acknowledges the Waldensians' right to discuss their religion in schools or other public places, if they are invited to do so. Waldensian pastors will also be allowed to celebrate marriages, a right the church has requested for the first time.
Perhaps the main benefit non-Roman Catholics will derive from the new Concordat and intesa is the change in religious instruction in schools. Children will no longer be taught the Roman Catholic religion automatically unless parents request an exemption (and go through a sometimes arduous process to secure it). On the contrary, parents will now have to make a special request if they want their children to be taught the Roman Catholic faith. The Waldensians' continuing interest in making the scriptures available to all is evidenced in the new Italian translation of the Bible. It is the equivalent, Bouchard suggests, of the English-language ''Good News for Modern Man.'' One-third of the translators were Waldensians, as is the chairman of the ecumenical Bible Society in Italy.
The Waldensians sprang into being as an evangelical lay movement in about 1175 in southern France and northern Italy. They were excommunicated by the Council of Verona of 1184. In the Middle Ages they were the best organized heresy (though they did not consider themselves heretics).
They spread east and north, merging in Bohemia with Jan Hus's pre-Reformation reformation, later turning Calvinist in France. In 1532 the synod of Cianforan - a church organization that could be described in New England terms as a cross between the Congregational and the Presbyterian models - formally decided to become Protestant.