According to the early twelfth-century Vita of Christina of Markyate, toads (thought to be both evil and poisonous) invaded the anchorite’s cell, squatting everywhere – even on her psalter. She held firmly to her manuscript and refused to give up singing the psalms in honour of Christ; the toads disappeared. Christina used her psalter both as book and as sung text, driving out the devils, the toads, by the dual power of the manuscript she held and the belief she espoused. Similarly, in Felix’s Life of Guthlac, when disguised fiends attack the future saint, Guthlac vanquishes them with a single sentence, the psalm verse: ‘His auditis beatus Guthlac exsurgens psallebat: Convertantur inimici mei retrorsum, et reliqua’ (‘Let my enemies be put to flight, etc.’). A psalm verse, the action of singing a psalm, and a psalter were potent weapons against evil in early medieval Britain and Ireland. The psalter could also quell enemies, a martial quality exemplified by the Cathach of St Columba, supposedly the copy of the Gallican psalter written by Columba in Ireland. ‘Cathach’ means ‘battler’, and the Cathach, enclosed in an appropriate reliquary, was carried into battle in the forefront of the Irish clans. In fact, the reliquary itself became so prominent in the national imagination that its purpose, preserving the psalter, was forgotten. In the nineteenth century, back in Ireland after two centuries in France, the reliquary was finally opened and the psalter rediscovered.