The office of Grand Sword Bearer goes back to the earliest days of Masonry (it’s mentioned in the second edition of Anderson’s Constitutions) and is patterned after an office bearer in London (and other cities), who carries the Lord Mayor’s sword before him during processions.
According to David J. Williamson, Grand Chaplain Emeritus of the Grand Lodge of New York, the sword is symbolic of the Mayor’s role as chief law enforcement officer.
In Grand Lodge, a Grand Sword Bearer is a living symbol of the Grand Master’s authority and responsibility to enforce the Landmarks, Constitutions, rules, and edicts of the Craft.
(Source: The Empire State Mason, Spring, 2012 & Emessay Notes May 2012)