Again, the Old Testament prophets often appealed to general principles of moral reasoning in criticizing the immorality of pagan nations (e.g., Amos 1–2). Arguments such as this utilize natural moral law and general philosophical principles of moral reasoning. In the New Testament, the apostles used philosophical argumentation and reasoning to proclaim Christ to unbelievers (see Acts 17:2–4, 17–31; 18:4; 19:8). Their practice was consistent with that of the Old Testament prophets in this regard.