Now on to the next step in the creation process: the descent of the “line” (Kav). As Ari words it, “After the aforementioned Tzimtzum … a single straight line extended from the light of the Ein Sof … from above to below, descending and developing into that ‘void’” . That’s to say that a lone projectile was made to extend out of God’s Being that originated in Him but lengthened “downward” all the way into our reality. The “line” is clearly an indication of a direct connection between God and creation, but what implications are we’re to draw from it?
Ramchal makes the point in Petachim 27-28 that this “line” speaks to God’s interactions with and His governance of the cosmos, as we’ll see.
He tells us there that everything that was to exist in the world has its roots in the aforementioned trace … and that the Infinite … interacts with those phenomena … (Petach 27) by means of the line of (i.e., that emanates from) Ein Sof which entered into the “emptiness” that contains the trace, is sequestered within it on every level, and is said to govern it from within. But the Infinite also stands outside of the trace and encompasses it, and is said to incorporate all of its abilities and to observe it from every angle and to thus govern it from without (Petach 28).
In other words, Ramchal understands the “line” as a sort of life-line, if you will — an umbilical cord — between ourselves and our Source who, while lying outside of the world nonetheless communes with it, albeit minimally, by means of a thin line rather than a shaft, ribbon, or full column of light.
 From The Tree of Life pp. 14-15 (with slight changes).
(c) 2011 Rabbi Yaakov Feldman
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