The Divine Journey Trilogy was written as a single arc told through three doorways. Each book stands alone, but together they trace a path from the first quiet question (who am I, really?) through the loosening of old beliefs to the final homecoming, the recognition of what was here all along.
If you are brand new to this work and want the gentlest possible on-ramp, begin with Behind the Curtain — a shorter gateway book that introduces the core ideas (the Trinity of Truth, the observer, karma, the natural state) before the trilogy explores them in depth. If you would rather start with the trilogy itself, the simplest answer is: start with Book One. Most readers do. It builds the foundation the other two rest on. But if a different book is calling to you, trust that. The series is designed to meet you where you are.