The Many Blessings of Parashat Vay'chi

Pirkei de-Rabbi Eliezer 52:6
From the day when the heavens and the earth were created no man was ill, (who) sneezed and lived, but in every place where he happened to be, whether on the way or in the market, and (when he) sneezed, his soul went out through his nostrils; until our father Jacob came and prayed for mercy concerning this, and he said before the Holy One, blessed be He: Sovereign of all the worlds! Do not take my soul from me until I have charged my sons and my household; and He was entreated of him, as it is said, "And it came to pass after these things, that one said to Joseph, Behold, thy father is sick" (Gen. 48:1). All the kings of the earth heard (thereof), and they wondered because there had been no one like him from the days when the heavens and earth had been created. Therefore a man is in duty bound to say to his fellow: Life! when the latter sneezes, for the death of the world was changed into light, as it is said, "His neesings flash forth light" (Job 41:18).

Each Friday night, parents gather their children around Shabbat tables to offer them words of blessing. This is the traditional text that is used:
The traditional blessing for a boy is:
יְשִׂמְךָ אֱלֹהִים כְּאֶפְרַיִם וְכִמְנַשֶּׁה
Y’simcha Elohim k’Ephraim v’kimenashe—
May God make you like Ephraim and Menashe.
The traditional blessing for a girl is:
יְשִׂמֵךְ אֱלֹהִים כְּשָׂרָה, רבקה, רחל ולאה
Y’simcha Elohim k’Sarah, Rivka, Rachel v’Leah
May God make you like Sarah, Rebecca, Rachel and Leah.
Parents then offer this blessing over all their children:

The Torah: A Woman's Commentary, p.284
Jacob has lifted Ephraim and Menasseh from the genealogy of Joseph and placed them in his own genealogical list. He does so in memory, as it were, of Rachel, Joseph's mother. This is a strong statement of family continuity--from Jacob to Joseph to Joseph's sons.

Rabbi Richard Levy
Just as Ephraim and Manasseh received their merit not through any acts of their own but only because they were alive and were descendants of Jacob (as are we all), so Jewish boys need not feel that their parents’ love is dependent on their accomplishments; they are beloved just because they are children. For Jewish girls, however, who might be inclined by society's prejudices to think that because they are girls they need not set their sights very high, the blessing hold them up to the highest models: may God make you like the greatest women the Torah knows - Sarah, Rebecca, Rachel, and Leah.”

Bereishit Rabbah 98:3
From this the Jews merited to say Kriat Shema, When Jacob called them together he asked if any of them had any complaint against Hashem. They responded, Hear Oh Israel [our father] just as you dont have any contention, neither do we; Hashem the Lord is The One and Only. Jacob responded by saying "blessed is the name of His kingdom for all eternity"

שְׁמַע יִשְׂרָאֵל יְהֹוָה אֱלֹהֵֽינוּ יְהֹוָה אֶחָד:
Hear, Israel: Adonai is our God, Adonai is One.

Pesachim 56a
What is the reason that we recite that passage: Blessed be the name of His glorious kingdom for ever and ever, even though it does not appear in the Torah? The Gemara answers: We recite it in accordance with that which Rabbi Shimon ben Lakish interpreted homiletically. As Rabbi Shimon ben Lakish said that it is written: “And Jacob called his sons and said, Gather around and I will tell you what will occur to you in the end of days” (Genesis 49:1). Jacob wanted to reveal to his sons when the complete redemption would arrive at the end of days (see Daniel 12:13), but the Divine Presence abandoned him, rendering him unable to prophesy. He said: Perhaps the Divine Presence has abandoned me because, Heaven forfend, one of my descendants is unfit, as was the case with my grandfather Abraham, from whom Ishmael emerged, and like my father Isaac, from whom Esau emerged. His sons said to him: Hear Israel, our father, the Lord is our God, the Lord is One. They said: Just as there is only one God in your heart, so too, there is only one in our hearts. At that moment Jacob our father said in praise: Blessed be the name of His glorious kingdom for ever and ever, as all his children were righteous. The Rabbis said: What should we do? Shall we recite this verse? But Moses our teacher did not say it in the Torah as part of Shema. Shall we not recite it? But Jacob said it. In order to resolve this dilemma they established that this passage should be recited surreptitiously. Rabbi Yitzḥak said that the school of Rabbi Ami said: This is analogous to the daughter of a king who smelled the fragrance of the dried spices stuck to the bottom of the pot and craved to eat them. What can she do? If she tells her servants to give it to her, she will be disgraced, as the dried spices are a contemptible food. However, if she does not say she wants to eat them, she will endure suffering. Her servants began to bring them to her surreptitiously. One should conduct himself in that manner in similar cases of uncertainty.

Midrash Rabba to Deuteronomy
When Moses went up to the heavens, he heard the angels praise God by saying, “Blessed [is His] Name, etc.” When he returned to earth, he taught it to the Jewish People. We say it in an undertone so as not to offend the angels. On Yom Kippur however, when we are considered like angels, we are permitted to say ברוך שם aloud.

Bereishit Rabbah 98:4
“And Jacob called unto his sons, and said: ‘Gather yourselves together, that I may reveal to you…’” (Gen 49:1). What Jacob was about to reveal to his sons was when the time of redemption was to come. But the Presence departed from him. So he said, “Could it be, God forbid, that my bed has produced an unfit son—as happened to Abraham, my father's father, out of whom sprang Ishmael, or as happened to my father Isaac, out of him sprang Esau?” His sons assured him of their steadfastness: “‘Hear, O Israel [our father], The Lord is our God, the Lord alone' [Deut 6:4]. Just as in your heart there's only the One, so in our hearts there is only the One.” Then our father Jacob pronounced for the first time the benediction “Blessed be the name whose glorious kingdom is forever and ever.”
Hence—it is reported in the name of R. Samuel—every day, morning and evening, Jews say, “In the cave of Machpelah [where you are at rest], ‘Hear, O Israel [our father].’ What you commanded us we still practice: ‘The Lord is our God, the Lord alone.’”

The Torah: A Modern Commentary (2005 edition), p.317
Every blessing bestowed by any of us is at the core a prayer, since it asks God to help accomplish what we ourselves cannot. Yet the blessing is more than a prayer, for it assigns a decisive role to the one who pronounces it. Placing his hands in the solemn act, the patriarch sees himself as God's co-worker and as an essential link between the generations. We cannot take God's place; but neither can God take the place of parents and grandparents in the shaping of children's future.
Jacob's blessing has often served as a classic example of prayer: It begins with an adoration, proceeds to thanksgiving, and only then turns to the petition. Jacob speaks of the God of his ancestors; this is his link with the past. God is the Sovereign both because of tradition and though personal experience and relationship. This remains the basic nature of Jewish worship: God is approached as the God of history, especially Jewish history, but beyond that each generation has to rediscover for itself the One who was the God of the Ancestors.
Jacob sees his life spread before him. He is aware of the continued presence of God and ackowledges it with deep feeling. Past and future are now fused. He knows in this moment that his own complex life is crowned with hope, a hope that is represented by the God of his forebears and by the two boys at his side. His life is completed; the blessing of Abraham, which Isaac had bestowed on him, has now passed down to his children's children.