Shabbat comes in 3.41pm; goes out 4.51pm
Modern science tells us the importance of a good hug; it actually releases dopamine in the brain which calms the receiver. This kind of physical contact is also important as Jacob, on his deathbed, blesses Ephraim, Menashe, and Joseph. His blessing is “May God…bless the lads. In them may my name be recalled, and the names of my fathers Abraham and Isaac, and may they be teeming multitudes upon the earth.”
The next verse in the Torah tells us just how Jacob gave the blessings. He placed a hand on each grandson, establishing physical contact. For this reason, when parents bless their children today, (usually at the start of the Shabbat meal) they too place a hand on the head of their children , to heighten the intimacy and communication through some form of physical contact during the blessing.
Rabbi Paul Arberman