Ignorantia Sacerdotum are the first words and also is the better-known title of De Informatione Simplicium, a catechetical manual drafted by Archbishop Pecham

John Peckham

John Peckham was Archbishop of Canterbury in the years 1279–1292. He was a native of Sussex who was educated at Lewes Priory and became a Franciscan friar about 1250. He studied at Paris under Bonaventure, where he later taught theology. From his teaching, he came into conflict with Thomas...

's provincial Council of Lambeth

Lambeth

Lambeth is a district of south London, England, and part of the London Borough of Lambeth. It is situated southeast of Charing Cross.-Toponymy:...

 in 1281. It called for the memorization of the Apostle's Creed, the Ten Commandments

Ten Commandments

The Ten Commandments, also known as the Decalogue , are a set of biblical principles relating to ethics and worship, which play a fundamental role in Judaism and most forms of Christianity. They include instructions to worship only God and to keep the Sabbath, and prohibitions against idolatry,...

, and the two-fold injunction to "love the Lord thy God with all thy heart... and thy neighbor as thyself."

It also emphasized the Seven Virtues

Seven virtues

In the Catholic catechism, the seven catholic virtues refer to the combination of two lists of virtues, the 4 cardinal virtues of prudence, justice, restraint or temperance, and courage or fortitude, and the 3 theological virtues of faith, hope, and love or charity ; these were adopted by the...

, the Seven Deadly Sins

Seven deadly sins

The 7 Deadly Sins, also known as the Capital Vices or Cardinal Sins, is a classification of objectionable vices that have been used since early Christian times to educate and instruct followers concerning fallen humanity's tendency to sin...

, the Seven Sacraments, and the Seven works of mercy.

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