And Jacob separated the lambs: lambs translates the Hebrew terms used in verses 33 and 35 and rendered lamb in Revised Standard Version and “sheep” in Good News Translation. Others translate “ewe,” meaning adult female sheep. In sheep raising cultures it will be advisable to use the term for “ewe.” We may also say, for example, “the sheep that were in heat” or “the female sheep that were ready to breed.” These female sheep are being bred while facing the colored animals in order that they will produce colored young for Jacob’s flocks. Accordingly in translation it may be necessary to make clear the reason Jacob set the faces of the flocks [these ewes] toward the striped and all black in the flock of Laban. See the note on trick 2 in verse 37.

It is obvious that Jacob cannot make his ewes face Laban’s animals if these are three days journey away (see 30.36). Since the process described takes place over a long period, we may assume that Laban’s animals and Jacob’s animals are again near each other, with Laban’s animals now carrying their owner’s markings. (Another possible explanation is that the colored animals referred to in this verse are the young ones bred by the trick described in verses 37-39, which at this time are still with Laban’s flock, even though they belong to Jacob.)

We may translate verse 40, for example:

• Jacob removed the ewes from the other sheep and goats in Laban’s flock. When these ewes were bred, he made them look toward the striped and black animals of Laban so they would give birth to striped and spotted young. By doing this he increased the number of his own animals and kept them separate from Laban’s herds.

A different possibility for this verse is given by Revised English Bible. It is that Jacob separated the rams (male sheep) of Laban’s flock and let only the colored rams breed with the ewes, thus making sure that the offspring would be black. While this is the way a modern sheep-breeder would think, it must be regarded as only speculation in this text and cannot be recommended to translators.

Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Genesis. (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .