Do you know what may very well be the most important book of the 1100s? If we were to dip back into the 1090s, we would say, “Oh, that’s easy. That’s Why the God-Man? by Anselm.” If we were to go into the 1200s, we’d probably say Thomas Aquinas’s Summa Theologica, that great massive work of theology. But what about the 1100s? What would be the most important book? Someone might say Peter Lombard’s Sentences, which was written around 1150. It was certainly a substantial book, and it was a classic text for centuries after it was written. I might be tempted to give that one a runner-up, however, and instead I’d go for the Glossa Ordinaria. It too was published right around 1150, and for about six hundred years, it was the standard annotations, or commentary, on the Bible.

Glossa literally means “language,” and when you gloss a text, that means you add an interpretive note, usually in the margin. A collection of these glosses is what we call a glossary. So we’re basically talking about expanded dictionary. And ordinaria? That means ordinary. It also means regular, or, to be technical, it means a standard form. So the Glossa Ordinaria, compiled around 1150, was the standard form annotations of the biblical text. This is a massive work. It was a collection of books, commentaries, and annotations on the Bible, and it did not just come in a vacuum. Let’s see how it came about.

Early in the centuries, monks and biblical scholars would write margin notes on the biblical text. As they would copy the biblical text, whether that was early in the Greek or the Hebrew or later when they focused on the Latin text, they would write little notes in the margins that would sometimes define or explain words. Sometimes they would have a note that was larger than the margin, and they would have to write it at the bottom of the page. The bottom of the page was called the foot of the page. The top, of course, was called the head. And so, notes written at the foot of the page came to be called footnotes.

You can imagine over the centuries how these notes would increase and accumulate, and so you would have notes all over the margins. You’d have notes all over the bottom of the page, and soon you couldn’t even see the text. So they began to collect these notes in a separate book, and then, of course, that grew to multiple books, and that’s what the Glossa Ordinaria is. It is multiple books of commentaries on the Bible.

Who did all this? Here are some names that you’re probably not familiar with. One of them is Walafrid Strabo. Strabo is from the 800s. He was born in 808 and died in 849 when he was forty-one years old. He was a German monk who wrote expositions of the Psalms and Leviticus. Following in his wake, a number of monks contributed various texts and commentaries. Bruno of Chartreuse wrote annotations on the Psalms and on Paul. Manegold of Lautenbach also contributed, and many other names that probably are not household names.

One more name is Anselm of Laon. We know the more popular Anselm, and this Anselm of Laon studied under the more famous Anselm. Anselm of Laon established a school of theology and a school of biblical hermeneutics. After his death, his students compiled collections of glosses—glossaries or commentaries on the Bible—and put them together in a big book, the standard text of biblical interpretation, the Glossa Ordinaria from 1150. It held sway for centuries as a standard text. (Thomas Aquinas followed suit for his Summa to do the same thing for theology.) This massive biblical text, the Glossa Ordinaria, was the twelfth century’s most important book.