Back in the time of the Temple, the Priests would bless the people with the Priestly Blessing, which was communicated by the LORD directly to Moses (in Numbers 4:24-26):
May YHWH bless you and guard you –
יְבָרֶכְךָ יְהוָה, וְיִשְׁמְרֶךָ
May YHWH make His face shine on you and show favor to you – יָאֵר יְהוָה פָּנָיו אֵלֶיךָ, וִיחֻנֶּךָּ
May YHWH lift up His face on you and give you peace – יִשָּׂא יְהוָה פָּנָיו אֵלֶיךָ, וְיָשֵׂם לְךָ שָׁלוֹם
In the Orthodox community, those men who are hereditary descendants of the ancient Priests, the Cohens, bless the rest of the community during the Amidah prayer with the Priestly Blessing. Their hands are placed in a peculiar shape, the form of the Hebrew letter shin (ש). Leonard Nimoy, raised Orthodox, saw the hands of the Cohens, and co-opted it as the Vulcan salute.
Masons are fascinated with all the rituals associated with the Temple, and as a mason, I feel inclined to point out what happens when you look at the actual Hebrew:
The first sentence is three words. The Tetragrammaton is the center word, flanked by a verb on either side. The first verb has root ברכ, or bless, which is where we get the name Baruch, (and in Arabic, Barack). The second sentence is five words, with the Tetragrammaton the second word, and the third sentence is seven words, with the Tetragrammaton the second word. The last two sentences share three words in common: the Tetragrammaton (without a verb for it to act upon), His face, and a preposition meaning "on you".
The numbers 3, 5, and 7 jump out of the blessing, and the 5 and the 7 have an inner core of 3. Having just delivered the Emblems lecture of the Master Mason degree to six candidates last Thursday night, the significance of this is very acute.
The lecture was well-received, and I have been asked by another lodge to deliver the lecture there for four candidates in two weeks.