Finally, the book’s style is exactly the style of Ibn al-Qayyim found throughout his writings, something obvious to anyone who has read his works attentively—especially those that deal with spiritual discipline, asceticism, and moral training. Many of the subjects he merely sketches here he explores in depth elsewhere, so that this work reads like a distillation of that side of his authorship: he selects only the choicest insights and most precious benefits, then adds subtleties, fine points, lessons, and admonitions that appear nowhere else.

Sources
As noted earlier, most of the material in the book consists of reflections, thoughts, and benefits the author reached through his own contemplation, while only a small portion is taken from other works. At times he names the author or source he is quoting, and at other times he omits any mention. Among the sources he cites are:
– Ibn Qutaybah: p. 3 and 116 of Tafsīr Gharīb al-Qurʾān, and pp. 14, 16, 129, 149 of Taʾwīl Mushkil al-Qurʾān.
– al-Zajjāj: pp. 19 and 116 of Maʿānī al-Qurʾān wa-Iʿrābuh.
– al-Wāḥidī: pp. 128 and 131 of al-Wasīṭ.
– Ibn al-Jawzī: p. 21 of Kashf Mushkil al-Ṣaḥīḥayn. He also quotes extensively—without attribution—from al-Mudhish; most of the passages on pp. 52–69, as well as other places, are drawn from it.
– Ibn Taymiyyah: pp. 12, 136, 153.
– He ascribes some passages to Kitāb al-Zuhd by Imām Aḥmad (p. 75) and to