The treatment of the ‘legal other’ in the laws and legal thought of Christians is illustrated well in terms of their approaches to: (1) natural law, as it applies to human beings regardless of their religion; (2) the State, and its relationship with institutional churches; and (3) human rights, and their promotion by the churches. Natural law has played a pivotal but much contested role historically in Christian thought. At its core is the divine commandment to love our neighbours as ourselves. Historically, Christianity has grappled with the scriptural principle to render to Caesar that which belongs to Caesar (Matthew 22.21). Today, churches employ a range of distinct but related approaches in order to work out the implications of this principle for the relations between churches and the States within which they carry out their mission. The emergence of human rights discourse has also stimulated churches to develop their own particular positions on the fundamental rights of the other in terms of the equality of all humans who are understood theologically to be created in the image or likeness of God. What follows examines comparatively the presence of these ideas in the laws and legal thought of Christians across a range of ecclesial traditions in global Christianity today. In so doing, it explores whether it is possible to identify principles of Christian law on ‘the other’.