du (Tal; drosos).
1. Formation of Dew:
Two things are necessary for the formation of dew, moisture and cold. In moist countries there is less dew because the change in temperature between day and night is too small. In the deserts where the change in temperature between day and night is sometimes as much as 40 degrees F., there is seldom dew because of lack of moisture in the atmosphere. Palestine is fortunate in being near the sea, so that there is always a large percentage of water vapor in the air. The skies are clear, and hence, there is rapid radiation beginning immediately after sunset, which cools the land and the air until the moisture is condensed and settles on cool objects. Air at a low temperature is not capable of holding as much water vapor in suspension as warm air. The ice pitcher furnishes an example of the formation of dew. Just as the drops of water form on the cool pitcher, so dew forms on rocks, grass and trees.
2. Value of Dew in Palestine:
In Palestine it does not rain from April to October, and were it not for the dew in summer all vegetation would perish. Dew and rain are equally important. If there is no rain the winter grass and harvests fail; if no dew, the late crops dry up and there is no fruit. Failure of either of these gifts of Nature would cause great want and hardship, but the failure of both would cause famine and death. Even on the edge of the great Syrian desert in Anti-Lebanon, beyond Jordan and in Sinai, a considerable vegetation of a certain kind flourishes in the summer, although there is not a drop of rain for six months. The dews are so heavy that the plants and trees are literally soaked with water at night, and they absorb sufficient moisture to more than supply the loss due to evaporation in the day. It is more surprising to one who has not seen it before to find a flourishing vineyard practically in the desert itself. Some of the small animals of the desert, such as the jerboa, seem to have no water supply except the dew. The dew forms most heavily on good conductors of heat, such as metals and stones, because they radiate their heat faster and cool the air around them. The wetting of Gideon's fleece (Jg 6:38) is an indication of the amount of dew formed, and the same phenomenon might be observed any clear night in summer in Palestine
3. Importance to Israel:
Dew was a present necessity to the people of Israel as it is today to the people of the same lands, so Yahweh says, "I will be as the dew unto Israel" (Ho 14:5). Dew and rain are of equal importance and are spoken of together in 1Ki 17:1. It was especially valued by the children of Israel in the desert, for it supplied the manna for their sustenance (Ex 16:13; Nu 11:9).
4. Symbol of Blessing:
Isaac in blessing Jacob asked that the "dew of heaven" (Ge 27:28) may be granted to him; that these things which make for fertility and prosperity may be his portion. "The remnant of Jacob shall be in the midst of many peoples as dew from Yahweh" (Mic 5:7), as a means of blessing to the nations. "Blessed of Yahweh for .... dew" (De 33:13).
5. Symbol of Refreshment:
Dew is the means of refreshing and reinvigorating all vegetation. Many Scripture references carry out this idea. The song of Moses says, "My speech shall distill as the dew" (De 32:2). "A cloud of dew" (Isa 18:4) refreshes the harvesters. "My head is filled with dew" (Song 5:2). "Like the dew of Hermon" (Ps 133:3). "Thou hast the dew of thy youth" (Ps 110:3). "Thy dew is as the dew of herbs" (Isa 26:19). Job said of the time of his prosperity, "The dew lieth all night upon my branch" (Job 29:19).
Other figures use dew as the symbol of stealth, of that which comes up unawares (2Sa 17:12), and of inconstancy (Ho 6:4; 13:3). God's knowledge covers the whole realm of the phenomena of Nature which are mysteries to man (Job 38:28; Pr 3:20).
Alfred H. Joy