四分律刪繁補闕行事鈔 1.63

1.63

然決判是非者，必總通律藏之旨，并識隨經之文；如上六師所明，乃可究斯教迹。故《十誦》云：比丘有三事決定知毘尼相：一本起，二結戒，三隨結。應思惟觀察二部戒律，并及義解、毘尼、增一，開遮輕重。如五大色，是不淨，遮；非色，淨，不遮。如是等，籌量本末已用也！《明了論》亦云：比丘能知五相，名解毘尼，不看他面。文略同上，廣如彼說。

However, to definitively judge right and wrong, one must comprehensively understand the intent of the Vinaya Piṭaka and be acquainted with the texts of the subsidiary scriptures; as explained by the six masters above, only then can one investigate these traces of the teaching. Thus the Daśādhyāya-vinaya says: "A bhikṣu has three matters through which he definitively knows the characteristics of the Vinaya: first, the origin; second, the formulation of the precept; third, the subsequent amendments. He should reflect upon and observe the precepts of the two assemblies, as well as the exegetical commentaries, the Vinaya, the Ekottara, allowance and prohibition, and lightness and heaviness. For instance, the five primary colors are impure and prohibited; non-colors are pure and not prohibited. In such matters, he applies them after deliberating the roots and branches!" The Vinayavibhāṣā also says: "A bhikṣu who can know five marks is said to understand the Vinaya and does not look to the faces of others." The text is roughly similar to the above; it is fully detailed as stated there.