How do we know that Lavan had no sons before Ya’akov’s arrival?
(30,27) “And Lavan said to him: If now I have found favor in your eyes, I have divined, and Hashem has blessed me for your sake.”
Rashi explains that after Ya’akov’s arrival, Lavan was blessed with sons, because it is clear that before his arrival he had no sons since it says Bereishis 29:6 "and behold, his daughter Rochel is coming with the sheep" - is it possible that Lavan had sons and still send his daughter to be amongst other shepherds?
But how is this a proof? Maybe he did have sons already but they were as yet too small to manage the sheep! However, if this was the case he should have sent Bilhah and Zilpah who were his daughters from concubines, not Rochel who was his daughter from his married wife. Because granted if he had no sons it makes sense that he sent Rochel because she was the one who would inherit his property since daughters from married wives take precedence over daughters from concubines in the laws of inheritance, and so she would take best care of the sheep. But if he had sons already who would be inheriting Lavan’s property before the daughters, why would Rochel care for the sheep more than Bilhah and Zilpah?.
How could one as righteous as Ya’akov commit such an act of swindling?
(30,37) “And Ya’akov took moist rods of trembling poplar and hazelnut and chestnut, and he peeled white streaks upon them, baring the white that was on the rods.”
Everyone is amazed how a completely righteous person such as Ya’akov could do such an act of swindling!
But we can explain that his actions were completely legitimate, because the agreement between him and Lavan was that any of the flock which had just one of the specified markings - speckled or spotted or brown, including ringed and striped animals - these would belong to Ya’akov. And the proof that the agreement was that only one sign was needed is from posuk 35 “And he removed on that day…all the brown among the sheep”. Just as there only one of the signs was required, so too in all the cases only one was required.
But Ya’akov was well aware of Lavan’s trickery, and he was afraid that he would claim that all three signs - speckled, spotted and brown - were needed. Therefore he peeled the rods and made with them just two of the signs, and thus any of the flock which had all three signs definitely belonged to Ya’akov, since one of the signs was not due to Ya’akov’s interference, and in reality one sign was enough according to their agreement.
Similarly, when he turned the faces of the flock towards the sheep which already had the signs, he covered up one of the signs. The proof for this is from posuk 40, which says that “he turned the faces of the animals towards the ringed ones and every brown one among Lavan’s animals” - only two of the signs are mentioned, but not the third.
Why did Lavan not mention the sign of the stone pillar?
(31,52) “This pile is a witness and this stone pillar (מצבה) is a witness, that I (Lavan) will not pass this pile to go to you, and that you shall not pass this pile and this stone pillar to come to me, to do harm.”
When Lavan was talking about his side of the treaty he did not say “that I will not pass this pile and this stone pillar to go to you”, because Ya’akov did not wish to accept a מצבה as an eternal sign for his own sake, because in the future the Torah would forbid them to his offspring and make it something loathsome to Hashem, as it says in Devarim 16:22 “you shall not set up a stone pillar which Hashem, your G-d, hates”. Even though it was beloved of Hashem in the days of the forefathers, it later became hated because it became associated with idol worship.
But for the needs of Lavan he accepted it as a sign, since it was not hated by Hashem at that time.