Genesis 30:40

40 Jacob put the little ones of the flock to one side by themselves. But he made the older ones face the striped and dark-colored animals that belonged to Laban. In that way, he made separate flocks for himself. He didn't put them with Laban's animals.

Genesis 30:40 Meaning and Commentary

Genesis 30:40

And Jacob did separate the lambs
The ringstraked, speckled, and spotted; and set the faces of the flocks,
that were all white, towards the ringstraked, and all the brown in the flock of Laban;
either to go before those that were all white, that they by looking at them might conceive and bring forth such, which was another artifice of Jacob's to increase his own sheep; or else he set at the water troughs the white sheep on one side of them, and on the opposite side the speckled ones that the same effect might also be produced the more successfully both by the rods and by the speckled lambs: and he put his own flocks by themselves, and put them not unto Laban's
cattle;
partly that they might not be mixed together, but kept distinct, that what was his property might be discerned from Laban's; and partly, lest his spotted ones, being mixed with Laban's white sheep, by continual looking at them, should conceive and bring forth such likewise, and so his flocks be lessened.

Genesis 30:40 In-Context

38 Then he placed the peeled branches in all of the stone tubs where the animals drank water. He placed them so they would be right in front of the flocks when they came to drink. The flocks were ready to mate when they came to drink.

39 So they mated in front of the branches. And they had little ones that were striped or speckled or spotted.

40 Jacob put the little ones of the flock to one side by themselves. But he made the older ones face the striped and dark-colored animals that belonged to Laban. In that way, he made separate flocks for himself. He didn't put them with Laban's animals.

41 Every time the stronger females were ready to mate, Jacob would place the branches in the stone tubs. He would place them in front of the animals so they would mate near the branches.

42 But if the animals were weak, he wouldn't place the branches there. So the weak animals went to Laban. And the strong ones went to Jacob.