Spanish monk, perhaps Asturian origin, which took its name from the monastery of San Martín de Liébana (Cantabria), where he/she professed and lived until he/she took charge of the Leonese Valcavado Abbey. It is possible that I was also born in this Cantabrian village. Manuscripts of this monk became very famous for the richness of his miniatures, painted according to the Mozarabic models with bright colors on a gold basis, with rich decoration on the capitals and margins.
Among his works are the comments and explanations of the Apocalypse, formed by twelve books in which explains the literal sense of the passages of the Apocalypse of San Juan and a doctrine concerning the incarnation of Christ. These manuscripts use the characteristics of the Mozarabic books, in what refers to writing and ornamental details, and its original dates back to the year 776. They are dedicated to his pupil and colleague Etherio, who was Bishop of Osma.
Author, convinced that the end of the world would occur on Sunday of Easter in the year 800, this trend finalist made the centerpiece of his comments. His work was widely read and copied in all the monasteries, Castile and Leon in the 9th, 12th and 13th centuries. The original has been lost, but several copies are preserved, including one placed in the chapter of the Cathedral of the Burgo de Osma, dated in the year 1086. Decorated with seventy-three miniatures which, apparently, were the work of several copyists (at least two, one of which was called Petrus). It seems that this copy was made in the monastery of Sahagún (León).