This study of the Lord's Prayer is a suitable reminder (if one was needed) that this is a foundational liturgical prayer for all Christians, and as such has played a key role in catechesis. Mahon's focus is on the use of the Lord's Prayer in Reformation catechesis – Catholic and Protestant – and its function in Reformation public worship and private prayer. The introduction sets as a backdrop the trial of Joan of Arc, and her refusal to say the Lord's Prayer publicly. Mahon conjectures that this was because it was normal to recite it at confession, and she had been refused this sacrament. A further chapter sketches the ritual functions of the prayer in medieval faith, and is heavily dependent on other secondary sources. Mahon's real interest is the sixteenth century, and in a further chapter close attention is paid to primary sources, especially Deitrich Kolde's German A fruitful mirror: or, Small handbook for Christians (1470), and the anonymous French Kalender of shepherds (1493), which was printed in English in 1500. Luther's Small catechism and Lutheran liturgies, Cranmer, and the Catholic catechism of Peter Canisius all are subject to close discussion. This is further traced in relation to the public liturgy, particularly Cranmer's Book of common prayer (1552). When turning her attention to lay use, Mahon notes that Cranmer's Primer of 1553 patterned private prayer after the Morning and Evening forms of public prayer. She gives very valuable insights into Luther's and Cranmer's understanding and use of the Pater Noster. Calvin is mentioned only in passing, and, regarding his use of the Lord's Prayer, incorrectly. It was not merely a biblical quotation; it could be recited in some contexts, and in others was expanded and improvised because it was regarded as the perfect pattern of prayer, as Kenneth Stevenson clearly demonstrated in his 2004 study of the Lord's Prayer. Although certainly not her focus, it is slightly odd that Mahon made no reference to David Clark's 2016 study of the origins and early interpretation of the Lord's Prayer. That said, Mahon's study will prove invaluable to those looking at sixteenth-century treatment of this foundational prayer.