GUIDO, monk of MONTECASSINO. — He flourished under Abbot Gerardo (1111–23) and was the teacher of Pietro Diacono (De viris illustribus Casinensis coenobii: PL 173, 1010), who calls him «vir in humana eruditiones clarissimus, religione et vita probatissima» (ibid., 1044–45). He was charged by «quibusdam venerabilibus fratribus» with putting ALBERIGO (v.), a monk of Montecassino, and perhaps educated by G. (A. Mirra, p. 35), had experienced at the age of 10, and whose fame had spread widely.
But G.’s work was not well received because «quamplura descripsit, quamplura dimisit», to such an extent that Alberico himself rewrote it, preserving only G.’s prologue (ed. F. Cancellieri [V. BIBLICA.], pp. 144–45; A. Mirra [V. BIBLICA.], p. 86). According to Pietro Diacono as well (loc. cit.), G. also wrote a history of the emperor Enrico (IV or VI), and some verses on the fate of the same Vision, all of which has been lost.