When Christ commissioned his twelve apostles and exhorted them to preach the gospel to all nations, he also told them that, when the time came for them to give witness, they should not carry what they would say premeditated in their heads; instead, the Holy Spirit would speak for them spontaneously in illa hora. It is curious to reflect, then, that the formidable array of sermon manuscripts and anthologies of material compiled to support preachers in their task that survives from the British Isles in the later Middle Ages betrays how little confidence medieval preachers reposed in the original dominical advice. Miracles now were in shorter supply than in gospel times, it was said, and so preachers were driven to the expediency of mere human assistance. The modern historian of the book, needless to say, has every reason to be grateful for this medieval failure of nerve.

Copious though the legacy of compilations for preaching may be, this is not to imply, of course, that there was never any such thing as the medieval preacher who acted according to strict evangelical precept and who preached as he felt the Holy Spirit had moved him. Necessarily, the efforts of such a man would, of their nature, have left no palpable traces to posterity, unless someone other than him troubled to make notes of his words before they evaporated in the air.