How do we know what constitutes orthodox beliefs?

Orthodoxy in Christianity is defined by adherence to the teachings that have been recognized by early church fathers, as well as by various ecumenical councils throughout history. These councils addressed key issues of doctrine, ultimately producing creeds that encapsulate foundational truths of the faith. Principles such as the Trinity, the authority of Scripture, and salvation through Christ's atonement are core tenets recognized as orthodox. When evaluating beliefs, it is essential to measure them against these established standards to understand what is considered orthodox within the faith community (e.g., Nicene Creed, Athanasian Creed).