The dew is a merciful provision the Lord hath ordained for moistening the plants and other productions of the earth in dry seasons, when there is no rain. And it is supposed, that the dew of the night is exactly in proportion to the heat of the day. But what I more particularly desire to notice respecting the dew is, the gracious condescension of the Lord, in resembling his blessings on his people to the figure of the dew. Hence, we read, by his servant the prophet Hosea, how the Lord saith, "I will be as the dew unto Israel." (Hosea 14:5) And how is that? The Lord answereth in another Scripture. "It tarrieth not for man, nor waiteth for the sons of men." (Micah 5:7) No predisposing cause in men, no, not even the wants or miseries of men, prompting the infinite mind of God to bestow his blessings. His love is before our misery, and his mercy makes no pause for our merit. Hence, we find numberless Scriptures speaking of the Lord's mercies under this figure. Jesus saith to the church, in a time when visiting her, "My head is filled with dew, and my locks with the drops of the night." (Song of Solomon 5:2) Hence, the resurrection of his people by grace, as hereafter to glory, is said to be "as the dew of herbs, and the earth shall cast out her dead." (Isaiah 26:19) meaning that as from the rich dews which fall upon the earth, the dry, withered, and apparently dead plants of the winter shall again bud, and break forth in the spring, so the dead and dying state of Christ's redeemed shall, from the dew of his birth, "revive as the corn, and grow as the vine." Hence, the doctrines of grace are said to be of the same refreshing quality as the dew. "My doctrine" (said Moses,) "shall drop as the rain, my speech shall distil as the dew, as the small rain upon the tender herb, and as the showers upon the grass." (Deuteronomy 32:2 and Deuteronomy 33:13)
See Rain