瑜伽論記 5.450

5.450

四語之中，初語總標，後三別釋。善說、善言、善論者，景云：體一義異故有此三。

Among the four [kinds of] speech, the first speech is a general designation, and the latter three are detailed explanations. Regarding 'well spoken' (subhāṣita), 'good words', and 'good discourse': Master Jing says that their essence is one but their meanings differ, hence there are these three.