What is the significance of the Royal Arch degree in Freemasonry?

The degree serves as the completion and coping stone of the Masonic system 21. Under the English Constitution, Masonry is defined as consisting of the three Craft degrees and the Holy Royal Arch, functioning as an expansion and completion of the Master Mason degree, of which it once formed part 1. W. J. Chetwode Crawley held that it is not a separate entity but a constituent part of a single legend, without which the symbolic structure is left incomplete 2.

Philosophically, Walter Leslie Wilmshurst reads the degree as representing the final stage of human regeneration and spiritual attainment 1. In Wilmshurst's interpretation, the preliminary Craft degrees provide the required moral discipline and self-purification, while the Royal Arch foreshadows spiritual fulfillment 1. He treats the degree's officers as psychological allegories: the three Principals signify attributes of spirit—Holiness, Royal Supremacy, and Functional Power—while the Sojourners typify the threefold aspects of the human personality 1.

Historically, eligibility for exaltation originally required a candidate to have served as a Past Master, which led to the practice of "Passing the Chair" to qualify brethren who had not governed a lodge 2. Eligibility was subsequently broadened to include Master Masons of four weeks' standing 2.