Born to a deeply religious family (one of his sisters was a nun, and three other brothers were priests), at a very young age Sabbatini dedicated himself to a religious life. He involved himself with the Congregazione dei Pii Operai (Congregation of Pious Workers), teaching religion to the children of the poor and manual laborers of Naples and helping perform mass at the Chiesa de San Nicola alla Caritá. In this church he was in charge of the so-called Congregazione dei Figlioli (Congregation of Sons).