The keystone in Freemasonry is a significant symbol, particularly in the context of the Royal Arch. It represents the essential element that holds the structure together, much like the keystone in an arch that is crucial for its stability. Albert Pike, in his work Morals and Dogma, describes the keystone as a fundamental law, charter, or constitution that embodies the fixed habits of thought of the people. He states, "The keystone of the Royal Arch of the great Temple of Liberty is a fundamental law charter or constitution; the expression of the fixed habits of thought of the people embodied in a written instrument... that cannot be hastily changed nor be violated with impunity but is sacred like the Ark of the Covenant of God which none could touch and live." This illustrates the keystone's role as a symbol of stability and permanence in both Masonic teachings and the broader context of liberty and governance.