四分律行事鈔資持記 2.284

2.284

怨逼中，初示相。有二：一逼己婬他，二為他婬己，開身免難，制心護體。遭婬尚易，持往尤難；自非久習淨心，直恐未逃刑網。善下，示護心法。本謂女根，故生染著；今為蛇火，乃生厭懼；以心隨境轉，必其然乎。

Under 'coerced by an enemy', he first shows the marks. There are two: 1. forcing oneself to engage in sexual intercourse with another; 2. being forced by another to engage in sexual intercourse with oneself. Bodily [intercourse] is permitted to escape disaster, while the mind is prohibited to protect the [precept-]essence. To suffer sexual intercourse is still easy, but to maintain [the mind] throughout is especially difficult; unless one has long cultivated a pure mind, one is truly afraid of not escaping the penal net. 'Good...' shows the method of protecting the mind. Originally perceiving it as a female organ, defiled attachment arose; now regarding it as a snake or fire, disgust and fear arise; since the mind turns in accordance with objects, this must surely be so.