The devotion to the Sacred Heart is perhaps the most widely practised of Catholic devotions, where the heart of Jesus is seen as a symbol of "God's endless and fervent love for all". Evidence such devotion dates to the eleventh and twelfth centuries in a number of Benedictine or Cistercian monasteries. It was also widely advocated by the well-known saints Bonaventure (d. 1274) and Gertrude (d. 1302). In this classic 18th century text by Jean Croiset, the author states his purpose for writing the book in the introduction: "It is hoped that the reflections here made, will help to convince many, of the reasons for practising these holy exercises, and teach them at the same time how to practise them with fruit." This text is a reproduction of "Devotion to the Sacred Heart of Jesus," London: Burns and Lambert 1863, by Jean Croiset (1656-1738) with numerous 17th - 19th-century Catholic illustrations of the sacred heart of Jesus.