The purpose of this study—on the border between philosophy and theology—is to outline a historical profile as to the most serious and culturally significant theological expression of the spiritual life of American Protestantism, a phenomenon that has not drawn much research attention in Italy.
The religious factor played a crucial role in the formation of the United States—many of America’s Protestant colonies were in fact meant to be havens for those persecuted for their faith. Thus, already in the seventeenth century, we find Anglicans and Lutherans, although the type of Protestantism that would determine American culture was Calvinism.
A mitigated form of Calvinism deriving from the tradition of East Central England spread starting from New England (Massachusetts, Plymouth, New Haven, Connecticut), the place early emigrants had chosen. The conception of God who, in an absolute way outside of time, predestines some to glory and others to damnation, with no consideration for human action, was substituted by the idea of a dual “covenant.” In the former, man was seen as having been able to reach eternal life through works of obedience; once Adam broke this covenant, God was seen as having granted a second kind of covenant, in which he would save man with his pure grace, by means of faith.
In the groups that migrated to America around the middle of the seventeenth century because of their non-alignment with the official English doctrines, a vibrant intellectual life developed contributing significantly to the formation of American theology. We may think of figures such as Thomas Shepard (1605-1649) or John Cotton (1584-1652). The idea that dominated the latter’s writings was that God had directly inspired their migration to a new land of the covenant between people and God.
The ecclesiology of these groups, named “Congregationalist” or “Independent,” saw the Church as a community of “elected,” where the “Elders” have the power and responsibility to lead. Church and state are two separate and concomitant institutions—having the same author, God, with man the common subject and the glory of God the common purpose. According to a theocratic ideal, only the members of the Church are citizens of the state in full right. The arguments developed in this context, especially by John Wise (1652-1725), prepared and supported a mentality that would find its vindication in the War of Independence (1775-1783) a century and a half later.
The dominant note of the New England theologians is a pragmatic attitude, which considers theology as a practical and not speculative discipline and assigns great importance to direct experience—the “Spirit” is the inspirational origin and the criterion of reference for the true believer and good works are the “sign” of His election.
Even though the Puritans were a unitarian movement, there were some variations: while Cotton was the unwavering advocate of the absoluteness of God’s initiative over the elect, others asserted that divine gratuitousness was somehow bound to a human response or human behaviour; these included Richard Sibbes (1577-1635), who argued that “though God’s Grace do all, yet we must give our consent.”
The second Puritan generation—intellectually less bright than the first, educated at the English universities of Oxford and Cambridge—had Harvard “College,” founded in 1636, as its reference point. The most influential authors of the second generation were Increase Mather (1639-1723) and Cotton Mather (1663-1728), who played a conservative role, and Solomon Stoddart (1643-1729), who followed a more liberalizing trend. From an ecclesiological perspective, there were movements opposed to the congregationalist approach supporting the autonomy of the individual church.
In praxis and doctrine, the turn of the seventeenth and eighteenth centuries saw the rigid Calvinist concept of God’s absolute dominion and His unconditional initiative threatened. A new problem arose—reduced religious fervor made the “confirmation” of divine election, conferring the right to full membership in the community of the faithful, less evident. Thus, the idea was asserted that the Spirit could act not only in a direct way, but also through certain means such as Scripture reading, prayer, etc.
The spread of the works by the Dutchman Jacobus Arminius (1560-1609) played an important role; he had developed his thought in reaction to Calvinist rigidity. Among other things, he argued that salvation cannot exclude human freedom and that divine Grace is not irresistible. Arminius’ doctrine was adopted by Anglicans in the eighteenth century and found many supporters in America as well: among them Samuel Johnson (1696-1772), who emphasized the capacity of human freedom in the face of its destiny. This is the initial sign of the passage from the dominance of Puritan thought to the intervention of Enlightenment Rationalism, which eventually came to prevail in American culture.
On the other hand, as early as the 1720s there was a phenomenon called the “Great Awakening,” characterized by a religious revival. A leading personality who well described and went beyond this phenomenon was Jonathan Edwards (1703-1758). Edwards stood as the defender of the absolute nature of divine sovereignty against all the liberalizing trends that diminished religious engagement favored. He claimed, among other things, the primacy of direct experience, wherein the profound unity between body and mind was evident. The proof of the truth of Christianity was to be found in experience, that overflowed natural experience with intensity and content. Moreover, he was convinced of the lack of difference between natural knowledge and supernatural knowledge, that is, the lack of continuity between nature and grace. Moreover, to reaffirm the absolute sovereignty of God, Edwards refuted the idea of freedom understood as self-determination, which would constitute a fact whose origin would not be God.  On the contrary, the human act of will coincides with the fascination for the good that seems greatest. The “Great Awakening,” of which Edwards was an exponent, constituted a fact that eroded and subverted the dominant Puritan ecclesiology and the consequent Puritan conception of church-state relations. The exaltation of individual experience downgraded the importance of the Church as institution, and the identification of moral religious value with interior emotion and freedom of expression weakened the significance of objective relationships, of authority and government.
Edward’s thought was highly criticized. Charles Chauncy (1705-1787) emphasized the value of human will and de-emphasized, albeit in a cautious way, the value of emotional signs as proof of faith; he also made a “liberal” revision of the concept of original sin in a revaluing of human effort and “good works.” An opposition to the principles of Calvinism took hold in the Congregationalist churches, heading in a rationalist and anti-Trinitarian direction. It is precisely in the Edwards-Chauncy opposition that the divergent channels that would furrow the soil of American Protestant thought throughout its history were formed: “orthodoxy” against “liberalism” tending towards more radical “secularism.” These two opposing positions developed during the nineteenth century.
On the one hand, there was the manifesto of “Unitarian Christianity” (1819), characterized by an anti-Trinitarian position, an emphasis on the role of man’s rational activity and free consent, and an optimistic estimate of human nature. The vast majority of churches in Massachusetts and Harvard College were under the influence of this new current.
On the other hand, in the area that remained orthodox and “Trinitarian,” two different currents were delineated: the one with moderate Calvinists (or Old Calvinists), and the one with Edwards’ followers, who placed their emphasis on the direct action of God’s grace in human activity, tying to the Revivalist Movement that periodically characterized American Protestant life. Samuel Hopkins (1721-1803) was among the leaders of this second current.
The danger and spread of liberalism provoked a rapprochement between the Old Calvinists and the Hopkinsians. This encouraged a Revival Movement (“Second Great Awakening”) tied to the personality of Timothy Dwight (1752-1817), president of Yale College. The concern to respond to problems posed by the adversaries prompted Dwight and his students to modify Hopkinsian Calvinism on the sensitive issue of freedom, which they conceived of as a true capacity to choose and the foundation of true and genuine responsibility. From the beginnings of the nineteenth century, therefore, the Revival phenomenon substantially reduced its claim to be an event of Grace disproportionate to any human dynamic. The new current was given the name of “New Haven Theology” and its greatest exponents were Nathaniel W. Taylor (1786-1858); Asa Mahan (1799-1889); Charles Grandison Finney (1792-1875).
Following the great deal of success achieved by the new trends, Conservatives accused them of having abandoned the basic principles of Calvinism, of being Pelagian, and of radically compromising themselves with Liberalism and Unitarianism. The stronghold of the reaction from the “Old School” was Princeton, College and Seminary, with Charles Hodge (1797-1878) as its most prominent exponent. He stressed the doctrinal aspects, recovering the value of the institutional Church as vehicle and guarantee of the whole of doctrine and religious life. Also critical of New England Theology was Mercersburg Theology (German Reformed Church), the sole relevant branch of systematic theology that was profoundly original with respect to the whole living tradition. Mercersburg Theology was a singular enterprise—its fundamental theme is Christ as real “mystical presence” in history, that continues in a living tradition, and the value of the sacraments as facts in which participation in Christ’s presence is fulfilled; however, it did not achieve a lasting presence in the American world. 
It was not the activity of the Conservatives that undermined New England Theology, but rather the blows from the persistent attack of the Liberal Movement.