"And the Lord spoke to Moses, saying: Speak to Aaron and to his sons, saying, In this way you shall bless the children of Israel, saying to them: May the Lord bless you and keep you. May the Lord shine the light of His face on you and bestow His favor on you. May the Lord lift up His face to you and grant you peace" (Numbers 6:22–26).

These fifteen Hebrew words constitute one of the oldest texts of Israelite tradition, recited to this day by the kohanim, or priestly class, in many synagogues, as well as by parents who bless their children on Friday night before the Sabbath dinner. It is the oldest piece of biblical writing ever discovered in an archaeological dig, appearing on fragments dating to the last days of Solomon's Temple. But what does it mean?

The text is highly unusual, a three-part formula where each part repeats a similar pattern. All three verses begin with "May the Lord . . . you" and end with "and . . . you," where the second half represents not just an equivalent of the first but a consequence: each act of God results in a bounty for us, His beneficiaries.  

There is also a sense of progression. The scholar Jacob Milgrom describes the three verses as "a rising crescendo of 3, 5, and 7 words, respectively." Indeed, a careful look suggests that each blessing adds a new spiritual element to what came before.

May the Lord bless you and keep you. "And keep you" (v'yishmerecha) is built from the verb "shamar." This is among the earliest concepts of the Bible. Adam is placed in the Garden of Eden "to work it and to keep it" (ul'shomro). When Cain inquires of God, "Am I my brother's keeper" (shomer), he is invoking the elementary responsibility to protect the life of his brother Abel. The word suggests the preservation of physical life in its minimal conditions of health and prosperity. Our first request of God, therefore, is that our lives be preserved, that we may enjoy the world we have been given rather than suffering the ubiquitous dangers of hunger, disease, and death.

May the Lord shine the light of His face on you and bestow His favor on you. As Robert Alter points out, the Hebrew expression "light of one's face" means "a showing of favor or affection." We are reminded of the light that shone from Moses' face when he came down from Mount Sinai—a light so bright that he had to wear a veil for the rest of his life. Here the light of God's face represents spiritual elevation, moral specialness, an acute kind of understanding that only human beings can achieve. As for the "favor" that is the result of this light, the Hebrew word (vihuneka) suggests a further differentiation: a setting apart, a chosenness, that is a consequence of God's special love for the people Israel.

May the Lord lift up His face to you and grant you peace. You have to achieve a high spiritual level indeed for God to lift His face up to yours. As the rabbis were fond of saying, "if it weren't written, no one would have dared say it." Yet this third blessing promises to raise us higher even than the angels—to a realm where material and spiritual success fuse and where chosenness becomes one with universal humanity. This realm the Bible consistently refers to as "peace," the highest goal to which mankind can strive.

The word shalom appears across the Bible not merely as the absence of war, but as a positive ideal of human completeness (related to the word shalem, or "complete"). It embraces the totality of man in his spiritual, physical, moral, and intellectual aspects. It is also the climax of the central Jewish prayer, the silent amidah that traditional Jews recite three times daily, uttering 19 blessings of which the last is a call for God to "grant peace" to all of us.

All this and more is packed into the fifteen words uttered in antiquity by Aaron and his descendants, infusing generations with a powerful vision of life lived under the favor of God.

David Hazony's first book, The Ten Commandments: How Our Most Ancient Moral Text Can Renew Modern Life, will be published by Scribner this coming September.