Give me a break
וישב ישראל בארץ מצרים בארץ גשן ויאחזו בה ויפרו וירבו מאד
And Israel dwelt in the land of Egypt, in the land of Goshen, and they populated it, becoming incredibly numerous.
ויחי יעקב בארץ מצרים שבע עשרה שנה ויהי ימי-יעקב שני חייו שבע שנים וארבעים ומאת שנה
And Yaakov lived in the land of Egypt 17 years, and it was that the days of the years of Yaakov’s life were 147 years.
Rashi asks an interesting question. Why is this parsha סתומה, literally blocked or sealed off? Every parsha, the way it appears in a Sefer Torah, is separated from the previous parsha with a certain amount of blank space. Consequently, you can easily spot the beginning of a parsha. Parshas Vayechi is the only exception. It has no blank space between it and the previous parsha. The last verse of parshas Vayigash runs right into parshas Vayechi (making the beginning harder to find). Rashi is bothered, why is this so? Rashi brings two answers, both from the Midrash, as follows:
1) This week’s parsha describes the death of Yaakov. Afterwards begins the story of the Egyptian enslavement of his descendants, the Jewish people. Chazal inform us that the enslavement began the moment Yaakov died. This is hinted to by making the parsha סתומה, without a break. There was no break between his death and the enslavement.
2) Yaakov knew he was about to die. The Torah describes Yaakov’s wish to reveal to his children what will be at the End of Days. Immediately upon gathering them, however, he proceeds to describe each of their qualities and provide prophetic insights into their characteristics. Why did he change his mind? Chazal inform us that Hashem didn’t want Yaakov to reveal these secrets, so this prophecy was נסתם ממנו, blocked off from him.
Where did Chazal get these answers? The fact that the Torah has no breaks between the two verses must be to indicate that the two are related in some way. This relationship and what it conveys is what produced these answers, but how?
The first answer, that there was no pause between Yaakov’s death and the enslavement, understands that the first verse, which describes the settling of the Jewish people in Egypt, as being a period of tranquility. They weren’t oppressed; in fact they were welcomed with open arms. The Egyptians were thankful to Yosef for all he had done for them and were excited to have his family join them in their land. All of this was while ויחי יעקב, Yaakov lived. After he died, everything changed. The enslavement began, and so ended their tranquility in Egypt. We could even say the opposite: Yaakov died because of the enslavement. Hashem shortened his life; he died at an age much younger than his forefathers. Hashem had to start the enslavement, which had been foretold, and wanted to spare Yaakov the pain of seeing his descendants tortured. This would be another way of understanding the two verses read together.
The second answer, that prophecy was blocked from Yaakov, preventing him from revealing the end of days to his children, is a totally different approach. The expression ויחי יעקב, and Yaakov lived, doesn’t appear by any of the other forefathers or foremothers. Why did the Torah exclusively use this expression for Yaakov? This is to teach us that the shechina, the Divine Presence, separated from Yaakov, removing his ability of prophecy. When Yaakov found out Yosef was still alive, the verse says ותחי רוח יעקב, the spirit of Yaakov was rejuvenated (literally “lived”). This means his power of prophecy, which had been inaccessible since he thought Yosef died, had returned. I would have thought that this power of prophecy remained with him the rest of his days, so the verse teaches me ויחי יעקב, and Yaakov lived, but not רוח יעקב, the spirit of Yaakov. His power of prophecy was immediately removed when he came to Egypt. Why? When Yaakov reunited with Yosef he said: אמותה הפעם אחרי ראותי את פניך, Now I can die since I have seen your face. That means he was already planning to give over to his children his last will and testament, which included informing them of what will happen at the end of days. Hashem didn’t want him to reveal that information, so He immediately removed Yaakov’s ability for prophecy.
From just the second verse it’s not clear why the shechina was removed from him, so the first verse is directly adjacent to the second and says וישב ישראל בארץ גושן, and Israel dwelled in the land of Goshen. Hashem knew it would be a disaster if everyone knew when the end of days would be. There were individuals who knew that the redemption from Egypt wouldn’t be in their lifetime. They therefore ignored Hashem and didn’t turn to Him to save them. They firmly settled in Egypt without any yearning to return to the land of Israel. The same would be true if people knew when the end of days was; earlier generations wouldn’t turn to Hashem for help. They’d give up hope. Hashem didn’t want that. They’d instead choose to set up permanent settlements in the foreign lands to which they were exiled, without hope or desire to return to the land of Israel. Hashem therefore hid from us when the end of days would be, so every generation would yearn for the redemption, and wouldn’t desire to permanently settle in exile.
We still haven’t reached our final redemption, but we are closer than ever before. For the first time in two millennia, the Jewish people have their homeland under their control again. Many of the prophecies regarding the end of days have already been fulfilled. But we still have a lot to do. Sin’as Chinam, baseless hatred, is what Chazal tell us caused this terribly long exile. Only Ahavas Chinam, baseless love, can end it.
With that, we finish Sefer Bereishis, the book of Genesis. חזק חזק ונתחזק 
 Based on the Kli Yakar to Genesis 47:28
 Ibid verse 27. This is the last verse of the previous parsha, Vayigash
 Ibid verse 28. This is the first verse of parshas Vayechi
 Ad. loc.
 Bereishis Rabbah 96:1
 The Kli Yakar mentions that the Midrash provides a third answer, that all the pain in the world was blocked from Yaakov. He provides an explanation for where that answer came from as well. He also says that upon a little contemplation it’s clear that Rashi felt this answer is the same as the first, and that’s why he didn’t bring it. After thinking about it, it’s still not clear to me how that is so
 Bereishis Rabbah loc. cit.
 Genesis 49:1. There is a dispute amongst the meforshim, if this means the end of the Egyptian enslavement or the culmination of human history with the coming of Moshiach. The Kli Yakar takes the second approach
 This brings out a glaring contradiction. If prophecy was removed from Yaakov, how could he then share prophetic insights about his children? The Torah Temimah (to Genesis loc. cit.) suggests that only prophecy about the end of days was blocked from Yaakov, but the rest of his prophetic powers remained
 Ibid 15:13
 Genesis 45:27
 Ibid 46:30
 It’s not clear to me if this fits with the simple reading of the verse (loc. cit.) where Yaakov gathered his children and told them he wished to reveal to them the end of days, and then proceeds to describe their qualities instead. Rashi ad. loc. quotes Pesachim 56a and Bereishis Rabbah 99:5 that that was his initial plan, but the shechina was removed from him, so he proceeded to talk about other things. It sounds like it was removed only at that moment, but not earlier. According to the Kli Yakar, if Yaakov hadn’t had prophecy in 17 years, why did he think now would be any different?
 The Kli Yakar quotes Tanchuma Yashan Vayechi § 9 (brought in Yalkut Shimoni § 157), which says that when Yaakov wanted to reveal the end to his children, Hashem rebuked him by saying: “You[r children will no longer] call to me, Yaakov” (Isaiah 43:22)
 The Kli Yakar laments that in his days (the late 16th century) there were many who build extremely fancy houses that were meant to last as a permanent structure, without any desire to return to their homeland. He felt that’s why Hashem left them there and didn’t redeem them
 Yoma 9b
 Orot HaKodesh III p. 323-234
 I tried finding a source for the custom to say this. The closest I found was the Rema to Orach Chaim 139:11 who writes that the verse in Joshua 1:8 לא ימוש ספר התורה הזה מפיך חזק ואמץ is where the custom to say חזק to someone who got an aliyah came from