Even though the development of the portable manuscript (hand-written) Bibles enhanced the transportability of the Scriptures, the arrival of the Dominican and Franciscan friars in Paris led to another transformation of the physical Bible. The friars traveled from place to place, preaching the Word of God and usually relying on the charity of faithful Christians. The new one-volume "Paris Bible" was in ideal format for the friars because it was portable, it was definitive, it was searchable, and it was available commercially. However, since friars commonly walked from place to place, the portable Bibles were a little cumbersome. Those Bibles fit into the saddle bag of a horse or donkey, but hardly fit into the folds of a friar's habit (robe). Thus, even smaller Bibles were developed called "pocket" Bibles. Each copy was commonly written in minute script, densely blocked on the page, and is so compact that it can encompass all parts of the Scriptures into a single small unit, an entire hand-written Bible in one consecutive book in a single binding. The parchment or vellum is sometimes so white and thin that it looks like tissue paper, almost weightless in its density. The pages often had tiny initials at the start of each text with red or blue penwork for chapter initials or other illustrations.
This leaf from a 13th century Latin manuscript "pocket" Bible was scribed in France. The text is from the end of the 3rd chapter of Zephaniah through the first two chapters of Haggai. The minute text, on very thin vellum, is handwritten and colored.
Biblical Heritage Gallery, Cedarville University, Pocket Manuscript Bibles