梵網經菩薩戒本疏 3.17

3.17

第二、釋名者，言非稱實為妄，令他領解為語。戒防此失，此從所治為名。《智論》十五云：「妄語者，不淨心，欲誑他，覆隱實，出異語，生口業，是名妄語。」解云：此中亦攝惡口、兩舌、綺語等三，從首為名，以過患相起故。《智論》云：「四種口業中，妄語最重故。復次但說妄語，已攝三事。復次諸法中，實為最大。若實語，四種正語皆已攝得。」

Second, explaining the name: words not matching reality constitute "false" (mṛṣā), and causing another to understand constitutes "speech" (vāda). The precept guards against this lapse, taking its name from what it remedies. The Dazhidulun, fascicle fifteen, states: "False speech means that with an impure mind, wishing to deceive another, concealing the truth, one utters disparate words, generating vocal karma; this is called false speech." Explanation: this also subsumes the other three—harsh speech, divisive speech, and frivolous speech—taking its name from the foremost, because their faults arise mutually. The Dazhidulun states: "Among the four kinds of vocal karma, false speech is the gravest. Furthermore, merely mentioning false speech already subsumes the other three matters. Furthermore, among all dharmas, truth is the greatest. If speech is truthful, the four kinds of right speech are all subsumed."