The Liber Fraternitatis is a handwritten codex dated 1446, composed of approximately 500 sewn parchment leaves. It preserves the two papal bulls of Eugene IV and Sixtus IV, issued for the renewal of the Hospitaller Order of Santo Spirito and its associated confraternity, along with autographs from both humble devotees and prominent figures from the social and political spheres. The confraternity members were required to serve at least once a year in the hospital, seek out the poor and needy in the streets and homes, assist with burials, and collect alms for the institution. Over time, signatures from renowned personalities and rulers from Italy and across Europe were added. The codex also includes the signature of Pope Saint John Paul II. This precious manuscript features two illuminated incipits at the beginning of the bulls that reestablished the hospital: one issued by Eugene IV in 1446 and the other by Sixtus IV in 1478, both followed by the signatures of the pope and the cardinals.
