Ignorantia sacerdotum

Ignorantia Sacerdotum are the first words and the better-known title of De Informatione Simplicium, a catechetical manual drafted by Archbishop Pecham's provincial Council of Lambeth in 1281. It called for the memorisation of the Apostle's Creed, the Ten Commandments, and the two-fold injunction to "love the Lord thy God with all thy heart... and thy neighbour as thyself."

It also emphasised the Seven Virtues, the Seven Deadly Sins, the Seven Sacraments, and the Seven Works of Mercy.

A 1357 translation into English is often called the Lay-Folk's Catechism.

References

Duffy, Eamon. The Stripping of the Altars: Traditional Religion in England 1400-1580. New Haven: Yale University Press, 1992. 55, 6.