In addition to the remains of the apostle, one of the most precious treasures kept in the cathedral of Santiago is the so-called Codex Calixtinus, also popularly known as "The first guide to the Camino de Santiago", written in the twelfth century.
The "Codex calixtinus" is a medieval manuscript dating from about the year 1140, which contains the oldest copy of the so-called “Liber Sancti Iacobi”, a compilation of masses, songs, sermons and miracles related to the Apostle Santiago. There are currently about twelve copies of this collection throughout Europe, the oldest being, as has already been said, the one kept in the cathedral.
The codex, or rather the "Liber Sancti Iacobi", begins with a letter supposedly written by Pope Calixto II (from which the name of the manuscript comes), and continues with five books, which contain:
- Liturgical texts (sermons, masses) related to the cult of the Apostle Santiago.
- Accounts of miracles performed by the apostle.
- An account of the transfer of the body of the saint to Compostela. (The first reference to shells as a symbol of the Jacobean pilgrimage appears in this book, when the first pilgrims picked them up on the beach as proof of their arrival in Santiago).
- An account of the entrance of Charlemagne on the Peninsula and the appearance of the apostle to him (Charlemagne's Iberian campaign includes his famous defeat in the battle of Roncesvalles, which inspired the famous Song of Roldán. These historical facts also appear in this book.)
- A medieval pilgrim's guide, with a list of rivers, towns, hostels, churches... that can be found on your journey.
This last book, the fifth, is the best known, and the one that has earned the codex the nickname of “First Pilgrim's Guide”. For decades, historians have relied on this book to find out details of the towns on the Camino, as they were during the Middle Ages, as well as the Jacobean pilgrimage during this time.
As for the authorship of the book, it has traditionally been attributed to the French monk Aymeric Picaud, who accompanied Pope Calixto II on his pilgrimage to Santiago in 1109, and who probably took advantage of his trip to compile the information that appears in the fifth book. However, said authorship is questioned today by some historians.
Finally, we cannot avoid reviewing the occasion in which the "Codex calixtinus", a manuscript with hundreds of years of history, made the front pages of newspapers in 2011, when it disappeared from the cathedral of Santiago. After several months of investigation, the police were finally able to recover it and arrest the culprit, an electrician who worked at the cathedral.
