Albert Barnes Commentary Job 38:28

"Hath the rain a father? Or who hath begotten the drops of dew?" — Job 38:28 (ASV)

Hath the rain a father? (Job 38:28) – That is, it is produced by God and not by man. No one among men can claim that he causes it, or can regard it as his offspring. The idea is that the production of rain is among the proofs of the wisdom and agency of God, and that it is caused in a way that demonstrates His own agency. It is not by any power of man, and it is not in such a way as to constitute a relation like that between a father and a son.

The rain is often appealed to in this book as something whose cause man could not explain, and as demonstrating the wisdom and supremacy of God. Among philosophic and contemplative minds, it would early excite inquiry and give occasion for wonder. What caused it? From where did the water which fell come? How was it suspended? How was it borne from place to place? How was it made to descend in drops, and why was it not poured down at once in floods?

Questions like these would early excite inquiry, and we should not suppose that in the time of Job science was so far advanced that they could be answered (see the notes on Job 26:8; compare with the notes on Job 38:37). The laws of the production of rain are now better understood, but like all other laws discovered by science, they are adapted to elevate, not to diminish, our conceptions of the wisdom of God. It may be of interest, and may serve to explain the passages in this book which refer to rain as illustrating the wisdom of God, to state what is now the commonly received theory of its cause.

That theory is the one proposed by Dr. James Hutton, and first published in the Philosophical Transactions of Edinburgh in 1784. In this theory, it is supposed that the cause consists in the vapor that is held dissolved in the air and is based on this principle: “that the capacity of the air for holding water in a state of vapor increases in a greater ratio than its temperature.”

That is, if there are two portions of air which would contain a certain quantity of water in solution if both were heated to an equal degree, their capacity for holding water would be alike. However, if one of them is heated more than the other, the amount of water it would hold in solution is not exactly in proportion to the heat applied, but increases much more rapidly than the heat.

It will hold much more water when the temperature is raised than is proportionate to the amount of heat applied. From the experiments which were made by Saussure and others, it was found that while the temperature of the air rises in arithmetical progression, the dissolving power of the air increases nearly in geometrical progression. That is, if the temperature is represented by the figures 2, 4, 6, 8, 10, etc., the capacity for holding moisture will be nearly represented by the figures 2, 8, 16, 32, 64, etc.

Rain is caused in the following manner: When two portions of air of different temperature, and each saturated with moisture, are intermixed, the quantity of moisture in the air thus intermixed, in consequence of the decrease of temperature, will be greater than the air will contain in solution, and will be condensed in a cloud or precipitated to the earth. This law of nature was of course unknown to Job, and is an arrangement which could have been formed only by the all-wise Author of nature (see the article "Meteorology" in the Edinburgh Encyclopedia, p. 181).

Or who hath begotten the drops of dew? (Job 38:28) – Who has produced them, implying that they were caused only by the agency of God? No one among mortals could claim that he had caused the dew to fall. God appeals to the dew here, the causes of which were then unknown, as an evidence of His wisdom and supremacy.

Dew is the moisture condensed from the atmosphere that settles on the earth. It usually falls on clear and calm nights and is caused by a reduction of the temperature of that on which the dew falls. Objects on the surface of the earth become colder than the atmosphere above them. Consequently, the moisture that was suspended in the atmosphere near the surface of the earth is condensed, in the same way that on a hot day moisture will form on the outside of a tumbler or pitcher filled with cold water. The coldness of the vessel containing the water condenses the moisture that was suspended in the surrounding atmosphere.

The cold, therefore, which accompanies dew, precedes instead of following it. The reason why the surface of the earth becomes cooler than the surrounding atmosphere at night, so as to form dew, has been a subject of considerable inquiry. The theory of Dr. Wells, which is now commonly adopted, is that the earth is continually radiating its heat to the high and colder regions of the atmosphere. In the daytime, the effects of this radiation are not sensible, being more than counterbalanced by the greater influx of heat from the direct influence of the sun. However, during the night, when the counteracting cause is removed, these effects become sensible and produce the reduction of temperature which causes dew.

The surface of the earth becomes cool by the heat that is radiated to the upper regions of the atmosphere, and the moisture in the air adjacent to the surface of the earth is condensed. This occurs only on a clear and calm night.

When the sky is cloudy, the clouds operate as a screen, preventing the radiation of heat to the higher regions of the atmosphere, and the surface of the earth and the surrounding atmosphere are kept at the same temperature (see the Edinburgh Encyclopedia, "Meteorology," pp. 185-188). Of course, these laws were unknown to Job, but now that they are known to us, they are no less a proof of the wisdom of God.