Articles of agreement among men are usually sealed, that the covenants may be the more solemn, and the performances of the covenants the more sure, to mutual satisfaction. God therefore, being willing more abundantly to show to the heirs of promise the immutability of his councils, has confirmed his covenant by a seal (Heb 6:17), which makes the foundations we build on stand sure, Ti2 2:19. The seal of this covenant of nature was natural enough; it was the rainbow, which, it is likely, was seen in the clouds before, when second causes concurred, but was never a seal of the covenant till now that it was made so by a divine institution. Now, concerning this seal of the covenant, observe, 1. This seal is affixed with repeated assurances of the truth of that promise of which it was designed to be the ratification: I do set my bow in the cloud (Gen 9:23); it shall be seen in the cloud (Gen 9:14), that the eye may affect the heart and confirm the faith; and it shall be the token of the covenant (Gen 9:12, Gen 9:13), and I will remember my covenant, that the waters shall no more become a flood, Gen 9:15. Nay, as if the Eternal Mind needed a memorandum, I will look upon it, that I may remember the everlasting covenant, Gen 9:16. Thus here is line upon line, that we might have sure and strong consolation who have laid hold of this hope. 2. The rainbow appears when the clouds are most disposed to wet, and returns after the rain; when we have most reason to fear the rain prevailing, then God shows this seal of the promise that it shall not prevail. Thus God obviates our fears with such encouragements as are both suitable and seasonable. 3. The thicker the cloud the brighter the bow in the cloud. Thus, as threatening afflictions abound, encouraging consolations much more abound, Co2 1:5. 4. The rainbow appears when one part of the sky is clear, which intimates mercy remembered in the midst of wrath; and the clouds are hemmed as it were with the rainbow, that they may not overspread the heavens, for the bow is coloured rain or the edges of a cloud gilded. 5. The rainbow is the reflection of the beams of the sun, which intimates that all the glory and significancy of the seals of the covenant are derived from Christ the Sun of righteousness, who is also described with a rainbow about his throne (Rev 4:3), and a rainbow upon his head (Rev 10:1), which intimates, not only his majesty, but his mediatorship. 6. The rainbow has fiery colours in it, to signify that though God will not again drown the world, yet, when the mystery of God shall be finished, the world shall be consumed by fire. 7. A bow bespeaks terror, but this bow has neither string nor arrow, as the bow ordained against the persecutors has (Psa 7:12, Psa 7:13), and a bow alone will do little execution. It is a bow, but it is directed upwards, not towards the earth; for the seals of the covenant were intended to comfort, not to terrify. 8. As God looks upon the bow, that he may remember the covenant, so should we, that we also may be ever mindful of the covenant, with faith and thankfulness.

I do set my bow in the cloud - On the origin and nature of the rainbow there had been a great variety of conjectures, till Anthony de Dominis, bishop of Spalatro, in a treatise of his published by Bartholus in 1611, partly suggested the true cause of this phenomenon, which was afterwards fully explained and demonstrated by Sir Isaac Newton. To enter into this subject here in detail would be improper; and therefore the less informed reader must have recourse to treatises on Optics for its full explanation. To readers in general it may be sufficient to say that the rainbow is a mere natural effect of a natural cause:

1.It is never seen but in showery weather.

2.Nor then unless the sun shines.

3.It never appears in any part of the heavens but in that opposite to the sun.

4.It never appears greater than a semicircle, but often much less.

5.It is always double, there being what is called the superior and inferior, or primary and secondary rainbow.

6.These bows exhibit the seven prismatic colors, red, orange, yellow, green, blue, indigo, and violet.

7.The whole of this phenomenon depends on the rays of the sun falling on spherical drops of water, and being in their passage through them, refracted and reflected.

The formation of the primary and secondary rainbow depends on the two following propositions;

1.When the sun shines on the drops of rain as they are falling, the rays that come from those drops to the eye of the spectator, after One reflection and Two refractions, produce the primary rainbow.

2.When the sun shines on the drops of rain as they are falling, the rays that come from those drops to the eye of the spectator after Two reflections and Two refractions, produce the secondary rainbow.

The illustration of these propositions must be sought in treatises on Optics, assisted by plates. From the well-known cause of this phenomenon It cannot be rationally supposed that there was no rainbow in the heavens before the time mentioned in the text, for as the rainbow is the natural effect of the sun's rays falling on drops of water, and of their being refracted and reflected by them, it must have appeared at different times from the creation of the sun and the atmosphere. Nor does the text intimate that the bow was now created for a sign to Noah and his posterity; but that what was formerly created, or rather that which was the necessary effect, in certain cases, of the creation of the sun and atmosphere, should now be considered by them as an unfailing token of their continual preservation from the waters of a deluge; therefore the text speaks of what had already been done, and not of what was now done, קשתי נתתי kashti nathatti, "My bow I have given, or put in the cloud;" as if he said: As surely as the rainbow is a necessary effect of sunshine in rain, and must continue such as long as the sun and atmosphere endure, so surely shall this earth be preserved from destruction by water; and its preservation shall be as necessary an effect of my promise as the rainbow is of the shining of the sun during a shower of rain.

I do set my bow in the cloud,.... Or "I have given", or "have set it" (p); which seems as if it was at that instant set; this is the same we call the "rainbow": and so Horace (q) calls it "arcus pluvius": it is called a "bow", because of its form, being a semicircle, and a "rainbow", because it is seen in a day of rain, and is a sign of it, or of its being quickly over, Eze 1:28 and this appears in a moist dewy cloud, neither very thick nor very thin, and is occasioned by the rays of the sun opposite to it, refracted on it: and this God calls "his bow", not only because made by him, for, notwithstanding the natural causes of it, the cloud and sun, the disposition of these to produce it, such a phenomenon is of God; but also because he appointed it to be a sign and token of his covenant with his creatures; so the Heathen poets (r) call the rainbow the messenger of Juno. It is a question whether there was a rainbow before the flood, and it is not easily answered; both Jews and Christians are divided about it; Saadiah thought there was one; but Aben Ezra disapproves of his opinion, and thinks it was first now made. The greater part of Christian interpreters are of the mind of Saadiah, that it was from the beginning, the natural causes of it, the sun and cloud, being before the flood; and that it was now after it only appointed to be a sign and token of the covenant; but though the natural causes of it did exist before, it does not follow, nor is it to be proved, that there was such a disposition of them to produce such an effect; and it might be so ordered in Providence, that there should not be any, that this might be entirely a new thing, and so a wonderful one, as the word for "token" (s) signifies; and the Greeks calls the rainbow the "daughter of Thaumas" or "Wonder" (t); and be the more fit to be a sign and token of the covenant, that God would no more destroy the earth with water; for otherwise, if this had been what Noah and his sons had been used to see, it can hardly be thought sufficient to take off their fears of a future inundation, which was the end and use it was to serve, as follows:

it shall be for a token of a covenant between me and the earth; that is, between God and the creatures of the earth; or of a promise that God would no more destroy the earth, and cut off the creatures in it by a flood; for though it is a bow, yet without arrows, and is not turned downwards towards the earth, but upwards towards heaven, and so is a token of mercy and kindness, and not of wrath and anger.

(p) "dedi", Montanus; so Ainsworth; "posui", Pisator, Drusius, Buxtorf. (q) De Arte Poetica, ver. 18. (r) Nuntia Junonis varios induta colores Concipit Iris aquas--------- Ovid. Metamorph. l. 1. Fab. 7. (s) "signum, tam nudum, quam prodigiosum", Buxtorf. (t) Plato in Theaeeteto, Plutarch. de Placit, Philosoph. 3, 4. Apollodor. Bibliothec. l. 1. p. 5.

RAINBOW. (Gen. 9:8-29)

I do set my bow in the cloud--set, that is, constitute or appoint. This common and familiar phenomenon being made the pledge of peace, its appearance when showers began to fall would be welcomed with the liveliest feelings of joy.