in Roman Catholic theology, the border place between heaven and hell where dwell those souls who, though not condemned to punishment, are deprived of the joy of eternal existence with God in heaven. The word is of Teutonic origin, meaning “border” or “anything joined on.” The concept of limbo probably developed in Europe in the Middle Ages but was never defined as a church dogma, and reference to it was omitted from the official catechism of the church that was issued in 1992. Two distinct kinds of limbo have been supposed to exist: (1) the limbus patrum (Latin: “fathers' limbo”), which is the place where the Old Testament saints were thought to be confined until they were liberated by Christ in his “descent into hell,” and (2) the limbus infantum, or limbus puerorum (“children's limbo”), which is the abode of those who have died without actual sin but whose original sin has not been washed away by baptism. This “children's limbo” included not only dead unbaptized infants but also the mentally impaired.

The question of the destiny of infants dying unbaptized presented itself to Christian theologians at a relatively early period. Generally speaking, it may be said that the Greek Fathers of the Church inclined to a cheerful view and the Latin Fathers to a gloomy view. Indeed, some of the Greek Fathers expressed opinions that are almost indistinguishable from the Pelagian view that children dying unbaptized might be admitted to eternal life, though not to the Kingdom of God. St. Augustine (Augustine, Saint) recoiled from such Pelagian teachings and drew a sharp antithesis between the state of the saved and that of the damned. Later theologians followed Augustine in rejecting the notion of any final place intermediate between heaven and hell, but they otherwise were inclined to take the mildest possible view of the destiny of the irresponsible and unbaptized.

The Roman Catholic Church in the 13th and 15th centuries made several authoritative declarations on the subject of limbo, stating that the souls of those who die in original sin only (i.e., unbaptized infants) descend into hell but are given lighter punishments than those souls guilty of actual sin. The damnation of infants and also the comparative lightness of their punishment thus became articles of faith, but the details of the place such souls occupy in hell or the nature of their actual punishment remained undetermined. From the Council of Trent (Trent, Council of) (1545–63) onward, there were considerable differences of opinion as to the extent of the infant souls' deprivation, with some theologians maintaining that the infants in limbo are affected with some degree of sadness because of a felt privation and other theologians holding that the infants enjoy every kind of natural felicity, as regards their souls now and their bodies after the resurrection.

The concept of limbo plays no role in contemporary Catholic theological thinking. In 2004 the International Theological Commission, an advisory body to the Vatican, under the direction of Joseph Cardinal Ratzinger (the future Pope Benedict XVI) began examining the question of limbo. In 2007 the commission, with the approval of Benedict, declared that the traditional view of limbo offered an “unduly restrictive view of salvation” and that there was hope that infants who died without being baptized would be saved.