The Liber Pontificalis ascribes to Pope Eleutherius a decree that no kind of food should be despised by Christians (Et hoc iterum firmavit ut nulla esca a Christianis repudiaretur, maxime fidelibus, quod Deus creavit, quæ tamen rationalis et humana est).
The Liberian Catalogue and the Liber Pontificalis date Linus's episcopate to 56–67, during the reign of Nero, but Jerome dates it to 67–78, and Eusebius puts the end of his episcopate at the second year of the reign of Titus (80).
The service book should not be confused with the collection of papal annals called Liber Pontificalis, probably first compiled in the 5th or 6th century.
Liber Pontificalis | Liber Septimus | Liber | Liber Exoniensis | Liber Abaci | Title page of the book ''Emblematum liber'' by Andrea Alciato | Mikhail Liber | Liber Gomorrhianus | Liber feudorum maior | Liber feudorum Ceritaniae | Liber de Causis | ''Liber chronicarum'' - more commonly known as the Nuremberg Chronicle | Artist's representation of distillation apparatus for aqua vitae, from ''Liber de arte Distillandi'', by Hieronymus Brunschwig |
According to the Liber Pontificalis, it was Alexander I who inserted the narration of the Last Supper (the Qui pridie) into the Catholic celebration of the Holy Sacrifice of the Mass.
According to Liutprand of Cremona (Antapodosis, ii. c. 48) and the "Liber Pontificalis," he was the natural son of Pope Sergius III (904–911), ("Johannes, natione Romanus ex patre Sergio papa," "Liber Pont." ed. Duchesne, II, 243).
The Liber Pontificalis credits John with making repairs to the cemetery of the martyrs Nereus and Achilleus on the Via Ardeatina, that of Saints Felix and Adauctus, and the cemetery of Priscilla.