Genesis 30:37-43
34 And Laban said, Behold, I would it might be according to thy word.
35 And he removed that day the he goats that were ringstraked and spotted, and all the she goats that were speckled and spotted, and every one that had some white in it, and all the brown among the sheep, and gave them into the hand of his sons.
36 And he set three days' journey betwixt himself and Jacob: and Jacob fed the rest of Laban's flocks.
37 And Jacob took him rods of green poplar, and of the hazel and chesnut tree; and pilled white strakes in them, and made the white appear which was in the rods.
38 And he set the rods which he had pilled before the flocks in the gutters in the watering troughs when the flocks came to drink, that they should conceive when they came to drink.
39 And the flocks conceived before the rods, and brought forth cattle ringstraked, speckled, and spotted.
40 And Jacob did separate the lambs, and set the faces of the flocks toward the ringstraked, and all the brown in the flock of Laban; and he put his own flocks by themselves, and put them not unto Laban's cattle.
41 And it came to pass, whensoever the stronger cattle did conceive, that Jacob laid the rods before the eyes of the cattle in the gutters, that they might conceive among the rods.
42 But when the cattle were feeble, he put them not in: so the feebler were Laban's, and the stronger Jacob's.
43 And the man increased exceedingly, and had much cattle, and maidservants, and menservants, and camels, and asses.
And Jacob took him rods of green poplar. The narration of Moses, at first sight, may seem absurd: for he either intends to censure holy Jacob as guilty of fraud, or to praise his industry. But from the context it will appear that this adroitness was not culpable. Let us then see how it is to be excused. Should any one contend that he was impelled to act as he did, by the numerous injuries of his father-in-law, and that he sought nothing but the reparation of former losses; the defence would perhaps be plausible: yet in the sight of God it is neither firm nor probable; for although we may be unjustly treated, we must not enter the contest with equal injustice. And were it permitted to avenge our own injuries, or to repair our own wrongs, there would be no place for legal judgments, and thence would arise horrible confusion. Therefore Jacob ought not to have resorted to this stratagem, for the purpose of producing degenerate cattle, but rather to have followed the rule which the Lord delivers by the mouth of Paul, that the faithful should study to overcome evil with good, (Rom. 12:21) This simplicity, I confess, ought to have been cultivated by Jacob, unless the Lord from heaven had commanded otherwise. But in this narrative there is a hysteron proteron, (a putting of the last first) for Moses first relates the fact, and then subjoins that Jacob had attempted nothing but by the command of God. Wherefore, it is not for those persons to claim him as their advocate, who oppose malignant and fraudulent men with fallacies like their own; because Jacob did not, of his own will, take license craftily to circumvent his father-in-law, by whom he had been unworthily deceived; but, pursuing the course prescribed to him by the Lord, kept himself within due bounds. In vain, also, according to my judgment, do some dispute whence Jacob learnt this; whether by long practice or by the teaching of his fathers; for it is possible, that he had been suddenly instructed respecting a matter previously unknown. If any one object, the absurdity of supposing, that this act of deceit was suggested by God; the answer is easy, that God s the author of no fraud, when he stretches out his hand to protect his servant. Nothing is more appropriate to him, and more in accordance with his justice, than that he should interpose as an avenger, when any injury is inflicted. But it is not our part to prescribe to him his method of acting. He suffered Laban to retain what he unjustly possessed; but in six years he withdrew his blessing from Laban, and transferred it to his servant Jacob. If an earthly judge condemns a thief to restore twofold or fourfold, no one complains: and why should we concede less to God, than to a mortal and perishing man? He had other methods in his power; but he purposed to connect his grace with the labour and diligence of Jacob, that he might openly repay to him those wages of which he had been long defrauded. For Laban was constrained to open his eyes, which being before shut, he had been accustomed to consume the sweat and even the blood of another. Moreover, as it respects physical causes, it is well known, that the sight of objects by the female has great effect on the form of the foetus. Now Jacob did three things. For first, he stripped the bark from twigs that he might make bare some white places by the incisions in the bark, and thus a varying and manifold colour was produced. Secondly, he chose the times when the males and females were assembled. Thirdly, he put the twigs in the waters. By the stronger cattle Moses may be understood to speak of those who bore in spring — by the feeble, those who bore in autumn.
And the man increased exceedingly. Moses added this for the purpose of showing that he was not made thus suddenly rich without a miracle. We shall see hereafter how great his wealth was. For being entirely destitute, he yet gathered out of nothing, greater riches than any man of moderate wealth could do in twenty or thirty years. And that no one may deem this fabulous, as not being in accordance with the usual method, Moses meets the objection by saying, that the holy man was enriched in an extraordinary manner.
— John Calvin (1509-1564)