For as the earth bringeth forth - This figure is several times used by the prophet (see the notes at Isaiah 45:8; Isaiah 55:10-11). The idea is an exceedingly beautiful one, that, on the coming of the Messiah, truth and righteousness would spring up and abound like grass and fruits in the vegetable world when the earth is watered with rain.
Her bud - The word ‘bud’ we now apply usually to the small bunch or protuberance on the branches of a plant, containing the rudiments of the future leaf or flower. The Hebrew word, however, (צמח tsemach), rather means the germ, the shoot, or the young and tender plant as it comes up from the earth; that which first appears from the seed.
So the Lord God will cause righteousness to spring forth - (See the notes at Isaiah 42:19; Isaiah 43:9; Isaiah 44:4; Isaiah 45:8).
Before all the nations - The sense is, that righteousness would abound over all the earth, and that all the world would yet join in celebrating the praises of God.