And pilled white streaks in them Pilled off the bark from the rods, at certain distances, till the white appeared between the bark. He set the rods in the gutters Or channels of water, at the time when the cattle were wont to couple, that their fancies might be painted with such divers colours as they saw in the rods. As it appears from Genesis 31:10, that God, to reward Jacob's fidelity, and punish Laban's injustice, determined that the cattle should generally be speckled and spotted; so it is probable he directed him to take this method to attain that end; not as though it were sufficient of itself to produce such an effect, which any person that will make the trial will find it is not; but as a means which God would bless in order to it, and which Jacob was required to use in testimony of his dependance on God, as Naaman was required to wash in the river Jordan, in order to his being cured of his leprosy. Much being said by authors concerning the surprising effects which impressions made upon the imaginations of pregnant animals will have upon the form, shape, and colour of the young, Dr. Shuckford observes, “1st, That it cannot be proved that the method which Jacob used is a natural and effectual way to produce variegated cattle; the ancient naturalists having carried their thoughts upon these subjects much further than they will bear; that the effect of impressions upon the imagination must be very accidental, because the objects that should cause them may or may not be taken notice of. But, 2d, Granting that they might naturally produce the effect here mentioned; yet if, as is probable, Jacob used the rods in obedience to a special divine direction, without knowing any thing of their natural virtue, the effect must still be ascribed immediately to God himself; just as in the case of Hezekiah, though the figs which were applied for his recovery might be a natural remedy for his distemper; yet, since the application of them was not made by any rules of physic then known, but by a divine direction, the cure is justly ascribed to the immediate hand of God.”
Related Commentaries of Genesis 30:37
Genesis 30:37-38
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.