Daoxuan describes a dichotomy, which perhaps is his own original idea, of inherently immoral actions or evils and hidden or concealed evils. The terms respectively are xìngè 性惡 and zhēxìng 遮性. The xìngè 性惡, or inherently evil actions, is defined by Daoxuan as follows.
Inherent evils are things such as killing and stealing which regardless if they are holy teachings, forbidden or not forbidden, if done are wrong and their essence being unwholesome. They are block the path and bring about retribution. Their damage and harm are deep and heavy and thus it is called inherently evil.
Zhēxìng 遮性 refers to Zhē'è 遮惡, or hidden evils, which is defined as follows.
Hidden evils are things such as tilling the soil and disrupting life or building domiciles. Before the Buddha regulated these activities to commit these things was in the nature of the karma only trivial. In essence they are not unwholesome. It is just that through these actions one disrupts things and prevents activities of practising the path.
I find this dichotomy useful to consider. Basically, there are actions which, either within a religious context or not, are by their nature evil and condemned by the majority, society and most individuals. Taking life, rape or stealing the property of others all are conducted with the intention to harm another and thus inevitably lead to one's own suffering. However, there are also hidden evils which by their nature are either neutral or trivial as Daoxuan points out, yet for the Buddhist practitioner are subtle hindrances towards development and realization. Daoxuan uses the example of building domiciles or tilling the soil, but this could also include playing games or passing the time in activities not in line with the dharma. These are subtle obstacles and are therefore potentially difficult to immediately detect.
Indeed, it is perhaps the subtle obstacles that we should concern ourselves with. Few of us would ever cultivate the intention to kill somebody, but we might fail to notice the subtle hindrances. As Hanfeizi points out the sages of old have a saying:
You don't trip over a mountain, but you trip over an anthill.
We need to be mindful of the little things.
1(CBETA, X41, no. 731, p. 569, c6-8 // Z 1:65, p. 225, d9-11 // R65, p. 450, b9-11)
2(CBETA, X41, no. 731, p. 569, c8-10 // Z 1:65, p. 225, d11-13 // R65, p. 450, b11-13)