Nothing But the Truth addresses the Christian's duty to hold the gospel firmly and defend it publicly in a culture that regards confident truth claims as arrogance. John MacArthur works through the biblical basis for contending for the faith, the nature of doubt and how Scripture treats it, the apologetic task and its limits, and the character required of those who would defend the truth without becoming quarrelsome.

The book suits believers who find themselves apologising for their convictions, students in hostile academic settings, and pastors preparing a congregation to give an answer. MacArthur distinguishes the courage Scripture commands from mere combativeness, which is the distinction most needed on this subject.