Silvestri's artworks on praying: gestures and symbols of meditation as  well as the key Christian prayer, the Our Father/ Pater Noster. In his book Le Ore e gli Oranti (Worship Hours), Silvestri's icons  illustrate and meditate the liturgy of the hours as well as the writings  of contemporary poets Maria Caterina and Lilia Grazie Tiberi (year of  publication 1999/2000 approximately).