四分律刪繁補闕行事鈔 1.98

1.98

三言戒行者。既受得此戒，秉之在心，必須廣修方便，撿察身口威儀之行；克志專崇，高慕前聖，持心後起，義順於前，名為戒行。故經云：雖非觸對，善修方便，可得清淨，文成驗矣。

Third, the 'precept practice.' Having received these precepts and holding them in the mind, one must cultivate skillful means broadly, inspecting and examining the conduct of the deportment of body and speech; dedicated in aspiration and exclusively reverent, admiring the ancient sages from afar, the mind of observance arises subsequently, its meaning conforming to what came before: this is called 'precept practice.' Thus a scripture states: 'Although it is not a matter of tangible contact, by cultivating skillful means well, one can attain purity'—this text is proof.