Two manuscripts from Petrarch's personal library concern the Pauline letters: Naples, Biblioteca San Luigi, Ar. I, 50, offering the full text of St Paul's letters with glossa ordinaria, and Paris, Bibliotheque Nationale de France, lat. 1762, containing Pauline commentaries by Ambrosiaster, Haimo of Auxerre, Jerome. Petrarch read and annotated both MSS: the Naples MS between 1350 and 1360; the Paris MS between 1360 and 1370. Maniculae, little flowers, notabilia, some other marginalia bear witness to a deep attention to scholarly questions and to moral and theological issues. Authors quoted are only St Augustine and Cicero. All the notes are here edited and commented, with cross references to Petrarch's marginalia in other MSS and to his works.