Describing his early considerations as to whether he should risk remonstrating against slander of the Lotus Sūtra, Nichiren wrote, “If I spoke out, I realized, the three obstacles and four devils would overtake me.” (Hori 2002, p. 53; see also 106-107) The “three obstacles and four devils” (J. sanshō-shima) are described in the writings of Tiantai Zhiyi (538-597). The following passage is a good example of Nichiren’s citing of this teaching and his explanation of it:

Therefore, it is stated in the Great Calming and Contemplation, fascicle five, “As practice and understanding of ‘calming and contemplation’ progress, the three obstacles and four devils compete to interfere with the practitioner. … Do not follow them or fear them. When one follows them, one will fall into the evil realms; and if one is afraid of them, one will be unable to master the True Dharma.” This is exactly what I have experienced with my own body. Also, this should be a clear mirror for my disciples and followers to reflect upon. Please practice with reverence, thereby producing nourishment for the future practitioners of the Lotus Sūtra.

The “three obstacles” in this citation refer to defilements, evil karma, and painful retributions. The defilements are the obstacles arising from the three poisons of greed, hatred, and delusion; evil karma refers to the obstructions arising from wives and children; and the painful retributions are obstructions caused by the rulers of a country, parents, and others. Among the “four devils” that cause hindrances is the king of devils in the sixth heaven in the ream of desire. (Hori 2010, p.adapted)

The three obstacles and the four devils were Zhiyi’s way of cataloging all the various phenomena that can keep us from practicing Buddhism. The three obstacles consist of self-centered desires or defilements, the karma or unwholesome habits that arise from those defilements, and the painful consequences of such activity.