Isaiah 32:4

The heart also of the rash shall understand knowledge, and the tongue of the stammerers shall be ready to speak plainly.

Ver. 4. The heart also of the rash.] Heb., Of the hasty ones, such as are headlong and inconsiderate, that weigh not things, that say not, What shall we do in the end thereof?

And the tongue of the stammerers.] That once did but bungle at holy discourse, pronouncing as it were Sibboleth for Shibboleth, and marring a good tale in the telling; as not understanding either what they say, or whereof they affirm. 1Ti 1:7

Shall be ready to speak plainly.] Shall be forward to speak fruitfully, having a holy dexterity therein. The Corinthians are commended for their utterance; 1Co 1:5 they could express themselves fitly, and they would do it freely.

To speak plainly.] Heb., Neat or clear words; limpida, nitida; a metaphor from clear or fair weather.