The name Guido returns several times in the history of Pomposa. When we are not talking about Abbot Guido (970 – 1046), who later became a saint, we are undoubtedly talking about the Benedictine monk who studied, taught, theorized and transformed the way music and its interpretation. Born in 922 ca. and died after 1033, the monk Guido is in Pomposa under the direction of the Abbot of the same name. His task was to prepare the young brothers for singing.
Singing the Divine Office, is one of the foundations of praise to God and his works (Opus Dei) and of Benedictine spiritual practice: it is a ritual prayer consisting of psalms, hymns, sacred passages and texts of the Fathers of the Church (secc. II-VIII). The chant not only accompanies the prayer but also prepares one for recollection and meditation. The Divine Office is recited collectively, daily, at certain hours of the day and night (the so-called canonical hours).
For centuries, it had become indispensable to have a specific teacher for singing monks since sacred chant continued to be handed down orally and in the West the liturgical musical tradition had settled on the Gregorian repertoire. To the figure of Pope Gregory I the Great (540? – 604), a Benedictine himself, was in fact attributed the regulation of sacred chants, collected and ordered in the Antiphonarius Cento.
Gregorian chant is performed a cappella, that is, without any accompanying instrument and each element of the choir sings in unison. The rhythm of the chant is derived from the syllables of the words and the melody.
The monk Guido was faced with the need to translate the rigor of the chants into simpler mnemonic terms than those in use. The custom was that the melody was learned to perfection through its continuous repetition, with the help of certain symbols, called neumes. Pinned above the text to indicate to the singer how to accompany the individual syllables musically, the neumes graphically replicated the grammatical accents of the French language and were used above all to remember whether the melody went up or down.
It is not by chance that it is above all the Benedictine monasteries that promote the development of graphic variants of these signs, which assume different characteristics according to the geographical area and increase in number. Among these changes are, at different times, the tracing above the liturgical text of the line of today’s FA (dry and then in red) and, above it, of the DO line (usually yellow).
In the eleventh century the use of a writing of the notes lines and spaces is already in use and musicians can rely on an interpretation at a glance.
Guido takes a further step, making a virtue of necessity. He employs a piece of music well known to singers and transforms this knowledge into a practical tool for musical learning. It is the first stanza of the Hymn to St. John:
«So that the faithful may sing with voices unfolded the wonders of your acts, dispel, Oh Saint John, the sin from the unclean lip.»
The monk isolates the notes corresponding to the initial syllables of each verse of the first stanza and identifies a scale of six sounds (hexachord): Ut, Re, Mi, Fa, Sol, La.

Ut queant laxis
Resonare fibris
Mira gestorum
Famuli tuorum
Solve polluti
Labii reatum,
Sancte Ioannes

This codification will make the singers more autonomous in reading at first sight the pieces and will lighten the effort of having to reproduce mnemonically all their passages.
The use of the parts of the hand to indicate to the singers the note to be played completes the range of didactic tools on which Guido relies for his teaching. It is not by chance that the reproduction in various manuscripts of the so-called “Guidonian hand” spread over time. (The cover image is a representation of the musical notation shown on the hand taken from, “Scientia artis musicae,” by Elia Salomon, 1274).

At least at the beginning, however, the intuition of the monk Guido is not received with great applause in the monastic environment.
But this is another story.