"Yesimcha Elokim k’Ephraim u’Menashe”
“May G-d make you like Ephraim and Menashe.”
One of the most beautiful customs in Jewish life is for parents to bless their children at the start of the Friday night Shabbat meal. Girls receive the blessing: "May God make you like the matriarchs Sarah, Rebecca, Rachel and Leah." Boys, meanwhile, are blessed "to be like Ephraim and Menashe."
What happened to the patriarchs Abraham, Isaac and Jacob?! Why were Ephraim and Menashe chosen instead as the subjects of this important tradition?
Ephraim and Menashe were the first set of Jewish brothers who did not fight. Abraham's two sons ― Isaac and Ishmael ― could not get along, and their disagreement forms the basis of the Arab-Israeli conflict until today. The next generation of Isaac's two sons ― Jacob and Esav ― were so contentious that Esav repeatedly sought to kill Jacob and instructed his descendants to do the same. And even the next generation of Jacob's sons sold Joseph into slavery in Egypt.
Ephraim and Menashe represent a break from this pattern. This explains why Jacob purposely switched his hands, blessing the younger Ephraim before the older Menashe. Jacob wished to emphasize the point that with these siblings, there is no rivalry. (see Genesis 48:13-14)
It is with this thought that parents bless their children today. For there is no greater blessing than peace among brothers. The words of King David ring true: "How good and pleasant is it for brothers to sit peacefully together." (Psalms 133:1)
Reaad full article by Rabbi Shraga Simmons: http://www.aish.com/tp/b/sw/48956426.html