Rashi adds: This means that when one blesses his own sons, he uses their blessing. Each man will say to his son: May God make you like Efraim and Menashe."

Rashi explains the verse and reiterates the sentiment. However it remains unclear to us why this "blessing" is necessary or what its particular content might be. Yosef knew that his father would eventually bless his sons and that the blessing to Yosef would naturally be inherited by his own children. What special need was there for a blessing now for the children of Yosef, while the other grandchildren would not be so blessed.

(verse 8) Yisrael saw Yosef's sons and said: Who are these? Yaakov tells his son Yosef about his own history and how it came to pass that his mother Rachel was not buried with the others. During this time Yaakov did not notice that the sons Efraim and Menashe were present, though he offered them (in absentia?) a special blessing. (verse 5) Your two sons…..are mine. Efraim and Menashe, are mine like Reuven and Shimon."

Rashi explains that this blessing is about inheritance of the land. "they are part of the total of my sons. They will take a portion of the promised land, just as my other sons.

Yaakov says to Yosef (verse 11), "I did not expect to see your face again, and G-d has shown me your children as well!"

This seems to indicate a second thought. After the blessing to Yosef's sons, that they will receive a portion of the land, Yaakov muses over the event. He has the opportunity to see his grandchildren, and that cannot go unnoticed. That is the moment at which Yaakov decided to give a special blessing to the grandchildren, and say that all the generations will see in this event a special model for imitation, and will bless their own children with this formula.

By "adopting" Efraim and Menashe, Yaakov was saying that the years spent in Egypt, unconnected to the tradition, and not having a proper teacher of Torah would not exclude the children from the tradition of learning which is a necessary prerequisite to achieving the status which enables inheritance of the land. The blessing is not only that the children are the children of Yaakov, but Yaakov assumes the role of the father. The traditions of Torah known to Yaakov are not directly passed on to the children of Yosef. The blessing that everyone gives their children is that they should have the opportunity offered to Efraim and Menashe, to learn Torah from the great teachers, even if the father is unable to play that role. This bracha was always seen by the Jews as primary, and offered again and again on Friday nights.

Gut Shabbos,
Chaim Brovender