The following monitorial instructions on the Symbolism of the Keystone appear on pp. 34-35 of “The Book of the Chapter” by Albert G. Mackey.

The following passages of Scripture are here appropriately introduced:

“This is the stone which was set at nought of you builders, which is become the head stone of the corner.” — Acts 4:11.

“To him that overcometh, will I give to eat of the hidden manna; and I will give him a white stone, and in the stone a new name written, which no man knoweth, saving he that receiveth it.” — Revelations 2:17.

“He that hath an ear to hear, let him hear.” — Revelations 3:13.

The Keystone, in this degree, is evidently an allusion to the tessera hospitales, or hospitable tokens, among the ancients, which have already been spoken of, and which are thus described by Dr. Adam Clarke:

“A small oblong square piece of wood, bone, stone, or ivory, was taken, and divided into two equal parts, on which each of the parties wrote his own name, and then interchanged it with the other. This was carefully preserved, and handed down, even to posterity, in the same family; and by producing this when they traveled, it gave a mutual claim to the bearers of kind reception and hospitable entertainment at each other’s houses.” [Clarke, Adam. New Testament with Commentary and Critical Notes, vol. II. p. 930.]

In the passage from the second chapter of Revelations, which is read during the presentation of the Keystone, it is most probable that by the “white stone” and the “new name,” St. John referred to these tokens of alliance and friendship. With these views, the symbolic allusion of the Keystone in the Mark degree is very apparent. It is intended to denote the firm and friendly alliance which exists between Mark Masters, and to indicate that by the possession of this token, and the new name inscribed upon it, and which is known only to those who have received it in the progress of their initiation, a covenant has been instituted that, in all future time, and under every circumstance of danger or distress, will secure the kind and friendly assistance of those who are the possessors of the same token. The Mark Master is thus, by the reception of this mystic sign, adopted into the fraternity of all other Mark Masons, and entitled to all the rights and privileges which belong exclusively to the partakers in the meaning of the same significant stone. The Keystone of a Mark Master is, therefore, the symbol of a fraternal covenant among those who are engaged in the common search after Divine Truth.

The full text of Mackey’s monitorial instructions on the Mark Master degree may be found at:

Mark Master from Mackey’s “The Book of the Chapter”