Note * — INTRODUCTION.
Reading edition
"The antiquity of illuminated missals has been traced, conjecturally, even to the time of the apostles themselves. At the beginning of the Christian era, missive letters were usually written on tablets of wood, hollowed so as to present something of the appearance of a boy's slate in a frame. Two of these were placed face to face to preserve the writing, which was on wax, and a pair of boards thus prepared was called a Dyptich. The Epistles of St. Paul and the other apostles to the primitive churches were, in fact, missive letters despatched to their distant congregations; and there is every probability that imaginary or real portraits of the writers accompanied the letters, and headed the contents of the Christian dyptichs, in order to insure to them the same degree of reverence which was paid to the missives of the government when headed by the imperial effigies.
"The compact form of the dyptich suited the purposes of a movable altar-piece admirably. And the names dyptic or triptic, which implied at first but a double or triple page, came with time to designate those folding altarpieces so frequently found in the earliest Christian churches."—Lady Calcott's Essay.