how does Mark Masonry and Royal Arch Masonry help a Master Mason develop further?

In the Craft, a Master Mason learns to govern his inner nature, having engaged in a search for the genuine secrets and divine potentialities lost to humanity 1. The Royal Arch acts as the completing part of this Masonic legend, serving as its cope-stone without which the symbolic building remains incomplete 2. Mystically, the Royal Arch sacramentally portrays the final stage of soul regeneration, depicting the journey out of earthly exile, through the veils of matter and form, into spiritual liberty and union with the All-Pervasive Spirit 1. Symbolically, its principal officers and sojourners represent the high attributes of the Spirit and the constituent parts of human personality, providing a psychological rationale for spiritual perfection 1.

In terms of symbolic instruction, Mark Masonry and the Royal Arch extend the candidate's understanding of the Temple narrative 3. While the Craft degrees set out the initial construction and tragedy, the broader degree sequence incorporating Mark and Royal Arch Masonry takes the Mason through the details of construction, the placement of secrets within a hidden vault, the destruction of the Temple, and its eventual rebuilding 3. In the Royal Arch, this culminates in the rediscovery of the lost secrets 3. Furthermore, ceremonies such as passing the veils represent super-physical stages a Mason must traverse to approach the light at the center 3.