Latin: labi, lapsus, to slip
- sacrificati, those who had actually offered a sacrifice to idols
- thurificati, those who had burnt incense on the altar of the gods
- libellatici, those who had drawn up or had caused to be drawn up certificates (libelli, several of which are still preserved) stating that they had offered sacrifice without, however, having actually done so.
After the edict of Decius (250-251) the lapsi who had obeyed the decrees out of weakness wished to attend Christian worship again. Pope Cornelius and Saint Cyprian of Carthage, who wrote a treatise entitled “De Lapsi,” favoured their return to the Church, and it was agreed in the synods held in 251 that they should be encouraged to repent and should be readmitted after performing certain public penance. This leniency met with opposition from Novatian, who claimed to be enforcing strict discipline, and finally formed a schismatic community. A new class of lapsi, called traditores, consisting mostly of clerics who yielded up the sacred books to the authorities, appeared during the persecution of Diocletian and caused many disputes, resulting ultimately in the Donatist schism. Canons for the treatment of the lapsi were drawn up by several synods, e.g., those of Elvira (306), Arles (314), and Ancyra (314), and the General Council of Nice. Libelli pacis were certificates of indulgence addressed to a bishop by confessors or martyrs petitioning that their merits be applied to remit the temporal punishment incurred by the lapsed Christians, who were known as libellatici (Latin: bearers of certificates).