Description (en)
The Imitation of Christ by Thomas a Kempis (1379/80 - 1471) is a widely read Christian devotional book. It was first published in Latin ca.1418, anonymously. It is the most important handbook for spiritual life and was popular among Catholics and Protestants. It is probably the most widely spread book of Christendom after the Bible. The authorship was debated for some time, but today Thomas a Kempis is generally accepted as the author.
http://en.wikipedia.org/wiki/The_Imitation_of_Christ