Visuddhimagga XVI-78

 Tathā passato vitakkayato ca taṃsampayuttāva vacīduccaritasamugghātikā micchāvācāya virati sammāvācā nāma. Sā pariggahalakkhaṇā, viramaṇarasā, micchāvācāppahānapaccupaṭṭhānā. 

[PTS 510]（三）有如上述的见及思惟（的瑜伽）者的与彼（正见正思惟）相应而断绝语的恶行的离于邪语为「正语」；和合语是它的特相，离（邪语）是它的作用，舍断邪语是它的现状。

Ñ(XVI,78): And when he sees and thinks thus, his abstinence from wrong speech, which abstinence is associated with that [right view], abolishes bad verbal conduct, [510] and that is called right speech. It has the characteristic of embracing. Its function is to abstain. It is manifested as the abandoning of wrong speech.