Libellus

A libellus (plural libelli) in the Roman Empire was any brief document written on individual pages (as opposed to scrolls or tablets), particularly official documents issued by governmental authorities.

The term libellus has particular historical significance for the libelli that were issued during the reign of Emperor Decius to citizens to certify performance of required pagan sacrifices in order to demonstrate loyalty to the authorities of the Roman Empire. During later periods libelli were issued as certificates of indulgence, in which the confessors or martyrs interceded for apostate Christians.

"Forty-six such certificates have been published, all dating from this same year [250 AD]." This particular year falls into the period of persecution under the emperor Decius. Four libelli were found among the thousands of papyri at the archaeological site near Oxyrhynchus in Egypt (P. Oxy. 658, P. Oxy. 1464, P. Oxy. 2990 and P. Oxy. 3929).

Participating in pagan sacrifices was a sin for Christians and punished by excommunication, because the New Testament forbade Christians to participate in "idol feasts". However, not participating made one liable to arrest by the Roman authorities. A warrant to arrest a Christian (P. Oxy. 3035) was also found at Oxyrhynchus, this too has been dated precisely—to the year 256. The grounds for this arrest are not documented, however, and it predates the persecution under the emperor Valerian by about a year.

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