Vayeshev has a number of themes in it that I could write about such as Yaakov's favoritism of Yosef over his brothers or the sibling rivalry that ensues causing almost fractricide. Yosef resisting temptation or his wife's master and then his keeping faith in God when it looked like He'd deserted him. Instead I want to look at the narratives of Yosef being sold and the story of Yehuda and Tamar.
I'm going to pick up the story with Yosef arriving to see how his brothers are doing.
18. And they saw him from afar, and when he had not yet drawn near to them, they plotted against him to put him to death.
19. So they said one to the other, "Behold, that dreamer is coming.
20. So now, let us kill him, and we will cast him into one of the pits, and we will say, 'A wild beast devoured him,' and we will see what will become of his dreams."
The original plan of the brothers (at least that of Shimon and Levi) is to kill their brother. Reuven enters the scene and has other plans. He wants to return Yosef back to his father by throwing him into a pit and then returning Yosef back to his father secretly. Reuven does not attempt to tell his brothers what he is really thinking because he realises they would not allow that.
21. But Reuven heard, and he saved him from their hands, and he said, "Let us not deal him a deadly blow." 22. And Reuven said to them, "Do not shed blood! Cast him into this pit, which is in the desert, but do not lay a hand upon him," in order to save him from their hands, to return him to his father.
Unfortunately Yehuda had other plans in mind. He neither wanted to kill Yosef or return him to his father. He wants to profit from Yosef by selling him.
26. And Yehuda said to his brothers, "What is the gain if we slay our brother and cover up his blood? 27. Come, let us sell him to the Ishmaelites, but our hand shall not be upon him, for he is our brother, our flesh." And his brothers hearkened.
Reuven comes back and is terrified that Yosef has been sold. He fears that Yaakov will blame him so they devise a plan to dip Yosef's tunic - the tunic that is the physical representation of their jealousy and enmity toward Yosef and dip it in animal blood to convince their father that Yosef was killed by a wild animal.
With no sensitivity whatsoever the brothers send the garment for Yaakov to identify the garment and understand that his son has been killed. PLEASE RECOGNIZE who does this tunic belong!
32. And they sent the fine woolen coat, and they brought [it] to their father, and they said, "We have found this; now recognize whether it is your son's coat or not."
The Torah goes on to tell that Yaakov goes into deep mourning and is not comforted by any of his family and that Yosef was sold to Potifar in Egypt. We expect the Torah to continue the narrative of Yosef's life in Egypt of becoming a successful slave to his master, of resisting the advances of Mrs. potifar and his subsequent imprisonment.
Instead we have the story of Yehuda and Tamar. Rashi explains that this story is mentioned here to tell us that when the brothers saw how melancholy their father was they regretted their actions but above all blamed Yehuda for them saying we listened to you when you said sell him had you told us to return him to father we would have done so. As a result Rashi says that Yehuda was lowered of his leadership of the brothers and he left them.
The Ibn Ezra explains that this story is to contrast Yosef and Mrs. Potifar with Yehuda and Tamar and that they are not at the same time.
Either way Yehuda leaves the family and marries a Canaanite woman - something expressly forbidden by Avraham, Yitzchak and Yaakov. In many ways this is Yehuda casting himself out of the family and this could be the end of the story.
Instead we hear that he has 3 children, Er, Onan and Shelah. Er is married off to Tamar and Er dies, then Onan marries Tamar through Yibum and he dies too. Shelah is not given to Tamar because he is too young. But the real reason is that Yehuda feels that Tamar is some sort of black widow.
A few years later, Yehuda's wife dies and Tamar realises that Yehuda has no intention of giving her Shelah as a third husband. She dresses up as a prostitute and Yehuda picks her up. She takes his signet ring, staff and cloak as collateral for a goat that will be given to her as payment for services rended. All the while Yehuda has no idea that the prostitute is Tamar.
Yehuda sends his friend Hira to find the prostitute and the townspeople tell him there is no prostitute in these parts. Hira and Yehuda cover their tracks and we here no more till 3 months time Yehuda is told that his daughter-in-law has got pregnant through harlotry. Yehuda still has no idea what has happened and calls for her to be burned.
As she is being taken out to be burned she sends the following message to Yehuda:
"From the man to whom these belong I am pregnant," and she said, "PLEASE RECOGNIZE whose signet ring, cloak, and staff are these?"
Yehuda recognizes them and saves Tamar from death. The phrase please recognize in Hebrew is הכר נא. That phrase only appears twice in the whole of the Tanakh both in our perasha. First when the brothers ask Yaakov to recognize Yosef's tunic and the second for Yehuda to recognize his staff, cloak and signet ring.
There is a deep significance to this phrase. Tamar was asking Yehuda not only to recognize the cloak, staff and signet ring she was asking Yehuda to recognize himself. Until this point Yehuda had been a selfish opportunist who was only interested in his own aggrandizement.
Tamar was taking a huge chance by sending a subtle message to Yehuda he could have concealed her secret by having her burned but he realized in himself what he had been doing all his life and something changed inside of him.
Until this moment the brothers had not spoken of selling Yosef even when in next week's perasha Shimon is taken captive, they still don't tell their father anything. The climax of the Yehuda and Tamar story is not in chronological order as Ibn Ezra and Rashi mentioned. The end of the story takes place just before Yaakov's family have run out of food and they must decide to take Binyamin with them or starve.
Tamar's actions were a seminal event in Yehuda's life he had the courage to put Binyamin's life ahead of his own. He was able to take back his leadership role amongst the brothers. Not a leadership by right but by deed. In the coming parshiyot of Miketz and Vayigash Yehuda proves himself and brings the family back together. But none of that could happen till Yehuda could recognize in himself what he had become and what he needed to be. Once he knew himself and his role he could lead the family. That is why it was him and not Yosef who eventually became the dominant tribe.
The rest is history. Yehuda and Tamar had twins Peretz and Zerach. Peretz is the ancestor of King David and the line of Mashiach. Out of this forbidden union and Yehuda's lowest depths comes the future redeemer of Israel. We all have low points in life and we all question ourselves it is how we deal with them and strive to improve that counts.