(כד) יְבָרֶכְךָ֥ ה' וְיִשְׁמְרֶֽךָ׃
(כה) יָאֵ֨ר ה' ׀ פָּנָ֛יו אֵלֶ֖יךָ וִֽיחֻנֶּֽךָּ׃
(כו) יִשָּׂ֨א ה' ׀ פָּנָיו֙ אֵלֶ֔יךָ וְיָשֵׂ֥ם לְךָ֖ שָׁלֽוֹם׃
(24) The LORD bless thee, and keep thee;
(25) The LORD make His face to shine upon thee, and be gracious unto thee;
(26) The LORD lift up His countenance upon thee, and give thee peace.
The kohanim (priests) bestow this blessing by lifting their hands above those who they are blessing. Why? What does it symbolize?
Each of the three blessings begin with the letter yod, which has the numerical value of 10.
Our sages taught, "Three share in the creation of a person. The father provides five elements -- the ligaments, the bones, the brain, the nails, and the whites of the eyes. The mother provides five elements -- the skin, the muscle, the blood, the hair, and the black of the eye. And the Holy One contributes the ten spiritual components -- ruach (spirit), n'shamah (soul), facial expression, sight, hearing, speech, walk, dei-ah (knowledge), binah (wisdom), and haskeil (enlightenment)."
These components, totaling twenty, are all blessed when the kohein lifts his ten fingers, and from each finger flows a double blessing--to the physical body and to the spiritual.
When the kohein lifts his hands, there should be a total of five spaces between his fingers. This must be done because it is written, "He is watching through the windows, peering through the lattices" (Song of Songs 2:9). Instead of "hacharakim / the lattices" read "hei/five charakim/lattices." And he must be very careful that the tips of his thumbs not touch each other, lest that window be spoiled.
Regardless of how this is done, it is important to remember that God is the one bestowing the blessings and the kohanim are only the conduits.
Sometimes it is hard to understand that the priests and those who are in a leadership are the ones who make things happen. However, we must realize that God is the One and that we are to understand that God is participating in our life and gives us these blessings. There is also a responsibility on our own shoulders to receive the blessing. In order for the kohanim to give the blessing, we must be there to receive it.