When the Rambam saw how Jewish life was deteriorating under the pressures of the exile, he created the Mishnah Torah as a guide to Jewish Law and philosophy. With his rigorous defense of human free will, and his distinct, "unmiraculous" view of the Messianic era, the Rambam was roundly criticized by many of his contemporaries. Though he did not back down on any philosophical issue, he acknowledged his error in omitting citations in his book. Rabbi Wein recounts the incident in which the Rambam came to this conclusion and points out the irony that his "book to end all books" has spawned thousands of commentaries since.