In Parshas Vayigash we read of the meeting, after a separation of many years, between Joseph and his father Jacob. The Torah states (Genesis 46:29):
ויאסר יוסף מרכבתו ויעל לקראת ישראל אביו גשנה וירא אליו ויפל על צואריו ויבך על צואריו עוד
Joseph harnessed his chariot and went up to greet his father, Israel, in Goshen, and he appeared before him and fell on his neck and cried for a long while.
It is hard for us to imagine the incredible sense of joy that Jacob must have experienced at this time, finally seeing his beloved son, whom he had thought dead for many years, and finding him to be not only alive and well, but a father and the ruler of the land of Egypt! Yet, in the description of the meeting, we find that it was Joseph who fell upon Jacob and cried, but Jacob is not described as doing anything at all!
יעקב לא נפל על צוארי יוסף ולא נשקו, ואמרו רבותינו, שהיה קורא את שמע:
Jacob did not fall upon the neck of Joseph, and did not kiss him. Our Sages say that he was reciting the Shema.
|R' Yehoshua Leib Diskin|
R' Yehoshua Leib Diskin's son, R' Yitzchak Yerucham Diskin (d.1925), expanded on this idea by pointing out that the basic theme of the Shema is the absolute unity of God. This means that God is the only power in the universe, and nothing happens - good or bad - outside of His control. This idea is in fundamental conflict with those worldviews that believe that good and bad come from separate powers, an idea that was basic to ancient paganism (and which still exists, in various forms, in modern times).
Thus, when Jacob finally met his son, and was able to see how all the suffering that he had experienced until now from the loss of his son had ultimately been for the benefit of his family, he attained a new level of recognition of God's dominion, and how there is no true distinction between what we perceive as good and what we perceive as bad. Thus, at that point he was inspired to recite the Shema and declare:
שמע ישראל ה' אלקינו ה' אחד
Hear O Israel, Hashem is our God, Hashem is One!