Patte's dictionary answers the question of what Christianity is not through an entry under that heading but through the whole of its three and a half thousand articles. Its working definition is deliberately wide: anyone claiming to follow Jesus Christ counts, which admits Catholics, Protestants, Orthodox and Anglicans alongside the fast-growing independent and charismatic churches and the groups usually filed as marginal.

No tradition serves as the benchmark. The volume avoids calling anyone a saint except where the word belongs to an institution's name or is plainly flagged as one church's judgement, and it uses the label heretic only where it is clear who is applying it.

Behind these choices lies an editorial commitment, argued by way of Spivak, neither to speak to nor to speak for believers in other cultural settings. Contributors present their own traditions; the historical coverage is anchored in a cluster of survey articles on world Christianity.