Many times in history, the Church intervened in the understanding of grace only when her people encountered certain doctrinal errors. Below are some historical examples or highlights:

Pelagianism This ancient yet constantly recurring error teaches that we human beings can achieve our salvation without the help of God's grace.

"A heresy concerning grace initiated by Pelagius (lived ca.400), a monk from Britain or Ireland, who, first in Rome and then in North Africa, taught that human beings can achieve salvation through their own sustained efforts. Original sin amounted to no more than Adam's bad example which did not harm interiorly his descendants and, in particular, left intact the natural use of free will. Reducing grace to the good example provided by Christ, Pelagius encouraged a strongly ascetical life and the emergence of a Church for the morally elite. Strongly opposed by St. Augustine of Hippo (345-430), Pelagianism was condemned by various councils in North Africa (DS 222-30), by two popes and in 431 by the Council of Ephesus (DS 267-68)." [Gerald O'Collins, S.J. and Edward G. Farrugia, S.J., Paulist Press, A Concise Dictionary of Theology, 1991, p.176]

Semi-Pelagianism This error teaches that we human beings can initiate our first step toward God without the help of God's grace.

"The view which derives from St. John Cassian of Marseilles (ca.360-435), St. Vincent of Lerins (d. before 450) and other monks in southern France, and according to which human beings can make their first step toward God without the help of divine grace. While accepting that grace is indispensable for salvation and so rejecting Pelagianism, those who developed Semi-Pelagianism (as it came to be called in the late sixteenth century) did so at least partly because of their opposition to the extreme version of predestination advanced by St. Augustine of Hippo (345-430). Eventually Semi-Pelagianism was condemned at the Second Council of Orange (529). Official church teaching, while following Augustine's teaching on grace (see DS 370-97; 2004-05; 2618; 2620), has never endorsed his interpretation on predestination." [A Concise Dictionary of Theology, pp.218-219]

Predestination This error teaches that, on the one hand, despite God's universal saving will and sufficient grace, some are pre-condemned for eternal damnation; and on the other hand, despite our free will which can totally reject God's grace, some are pre-elected for eternal salvation.

"(Lat. "being fore-ordained"). Being elected for salvation through the eternal foreknowledge and will of God (see Matt 20:23; Jn 10:29; Rom 8:28-30; Eph 1:3-14). The Pelagian controversy provoked from St. Augustine of Hippo (354-430) some extreme assertions about God electing (from the 'mass of sin" which is the human race) only some for eternal salvation." (A Concise Dictionary of Theology, p.190)

Calvinism There is an aspect in Calvinism which is clearly erroneous, i.e., the theory of double predestination, as further explained below.

"Disallowing the universal saving will of God, John Calvin (1509-64) held a double predestination: some human beings are elected by God for eternal salvation and others for eternal damnation. This view had been held by the monk Gottschalk (ca.804-ca.869), and condemned at synods in Mainz and Quiercy (see DS 621, 685, 1567). While properly vindicating the primacy of the divine grace on which we depend utterly, predestination should not be pushed to the point of denying either God's universal saving will (1Tim 2:3-6) or human freedom." (A Concise Dictionary of Theology, p.190)

Jansenism Despite their stress on God's efficacious grace, Jansenists were pessimistic about human nature. They preached and practiced an inflexibly strict morality. They were also quite scrupulous about the reception of the sacraments. [cf. A Concise Dictionary of Theology, pp.110-111] They do not seem to believe and trust in God's gracious mercy sufficiently.

"This movement, so called because of its origins in the teaching of Cornelius Otto Jansen (1585-1638), bishop of Ghent and later of Ypres, developed in France after c.1640 and persisted through the eighteenth century. It maintained an extreme form of St. Augustine's doctrine of grace, conceived as irresistible, and also a severe moral rigorism… But in the seventeenth century the nuns of the Convent of Port-Royal were caught up into the controversy, refusing to subscribe to the papal condemnation of Jansenism. A further papal bull (Unigenitus, 1713) condemned Jansenism; its supporters, being persecuted in France, migrated to the Netherlands. Eventually the Dutch Jansenists opted for schism and chose for themselves a bishop of Utrech (1723). This was the origin of the Old Catholics, though they have been joined by other groups of formerly Roman Catholics churches since that date." [Alan Richardson, A Dictionary of Christian Theology, SCM Press Ltd., 1969, p.175]

Molinism This theological theory is put here as an example to show the limit of human minds in explaining God's ineffable mystery.

"The Doctrine developed by the Spanish Jesuit Louis de Molina (1535-1600) about the relationship between free will and grace. God gives grace, arranges circumstances to bring about the proper result and foresees our future actions. But since this foresight 'depends' upon our free decisions, Molina called it scientia conditionata or scientia media: knowledge relative to future human decisions and actions. This system was opposed by the Dominicans, especially by Domingo Banez (1528-1604). In emphasizing God's sovereign freedom, Banez spoke of the divine concurrence in human action as praemotio physica (Lat. "physical pre-motion), an idea which does not seem to do full justice to human freedom. Between 1598 and 1607 a commission, 'De Auxiliis' met in Rome but failed to resolve the issue. It ended by forbidding Jesuits to brand the Dominicans as 'Calvinists' and the Dominicans to call Jesuits 'Pelagians' (see DS 1997, 2008). This debate indicates how the deepest theological questions cannot finally be answered adequately. The divine mystery has the first and the last word." (A Concise Dictionary of Theology, pp.145-46)

*********************************************************