The movement toward equality of persons is centuries old, and, despite occasional setbacks, it will continue. It is typically impossible to determine the exact weight of various influences on moral, political, and cultural ideas, but within the Western tradition, movements within Christianity have contributed significantly, in ways that the Introduction to this volume outlines, to our concepts of equality. Perhaps the most fundamental insight is that human beings are equal in the sight of God. As Paul wrote in his Letter to the Galatians: “there are no more distinctions between Jew and Greek, slave and free, male and female, but all of you are one in Christ Jesus.” Of course, in its origins, this understanding was spiritual, not implying that social and legal distinctions, such as that between master and slaves, should disappear. In the history of the Christian church, this basic sense of equality did affect the internal life of some small religious communities; on the other hand, the strong sense of hierarchy in the Roman Catholic Church and the deep convictions that Christianity was true and other religions were false both helped to sustain social and legal distinctions at odds with modern ideals of equality.

The Protestant emphasis on the “priesthood of all believers” and its strong individualism, as well as the powerful equalitarian premises of discrete groups such as the Levellers, helped to lay the foundation for broader notions of political and legal equality that emerged from the Enlightenment.