Packer’s influence weaves widely through three interconnected Christian sects, all of which formed the greater part of the initial audience for Knowing God: Anglicans, evangelicals, and Reformed/Calvinist theological circles. These groups overlap in various ways, and an understanding of their interactions can help set the theology and spirituality of Knowing God in its proper context.

Anglicanism is a broad and varied denominational tradition that stemmed from the English Reformation of the 16th century. “Anglican” refers to any church or group of churches in communion with the Church of England (or, in some cases, those that are derived from its theological heritage, even if not in direct communion). Such churches generally retain the name “Anglican” in their title, except in the United States, where the main Anglican denomination is the Episcopal church. Anglicanism is the third-largest denominational communion in global Christianity, after only Roman Catholicism and Eastern Orthodoxy. As a Protestant denomination, it emphasizes the centrality of Scripture but retains more of the classical liturgical and sacramental heritage of the medieval Christian tradition than most other Protestant churches. As such, it has often been called a via media (“middle way”) between Catholicism and Protestantism. The expression of Anglicanism in any given church can range from high-church (with a focus on liturgy, ritual, sacraments, and hierarchical structure) to low-church (prioritizing preaching, congregational worship, and a personal relationship between God and the individual). Packer’s brand of Anglicanism tended to fall along low-church lines, which accorded more closely with an evangelical Protestant ethos than with a Catholic one.

Evangelicalism is not a denominational tradition, but a cross-denominational movement within confessional Protestantism, which emphasizes a commitment to formalized elements of Christian doctrine. Individual churches or believers may identify as evangelical even when their broader denomination might not be considered evangelical in its totality, as is the case with Anglicanism. Evangelicals are represented in many Protestant denominations, but most frequently in low-church traditions like the Baptists, Wesleyans, Calvary Chapel, Bible churches, and many non-denominational and independent churches. Evangelicalism emerged in England and North America in the 1700s, drawing both from the Puritan theological heritage and the fervor of the Great Awakening. It is marked by an emphasis on the Bible as the inspired Word of God, a focus on the death of Jesus Christ on the cross as the central act of God’s plan of salvation, and an insistence that Christians ought to be spreading the good news of the gospel message to others. The first two of these emphases exercise a significant influence throughout Packer’s Knowing God.

The theological circles in which Packer operated are variously referred to as Calvinist or Reformed. This theological position was widely adopted following the work of John Calvin, a leading figure of the 16th-century Reformation, and most of the communions that adopted Calvin’s theology are referred to as Reformed churches (this includes, for example, Presbyterians and the Dutch Reformed Church). Reformed theology had a major influence on Anglicanism’s early development, but not a dominating influence, such that Anglicanism, while it has certain Reformed elements in its founding documents, is not usually considered a Calvinist tradition (but one may certainly find a few Calvinist theologians within it). The Puritans were a leading example of a Reformed theological movement existing under the larger umbrella of Anglicanism. Reformed/Calvinist theology focuses on the sovereignty of God, which leads to an overriding emphasis on divine action as the causative element in every part of a Christian’s salvation and spiritual growth. This emphasis is evident in several places in Knowing God, such as in Chapter 22’s focus on God’s actions in choosing, justifying, sanctifying, and protecting Christian believers.