Boundaries: 2

The transition from an infinite existence to one which is bounded also creates a distancing from the source. That which was previously omnipresent, is no longer. This is what our Sages refer to as the left hand (גבורה, the ability to create distinctions which is on the left side of the Sefiros Tree) pushing away, שמאל דוחה.
The distant vacuum that is created sucks a person towards it. This is referred to as the סיטרא אחרא, the other side. Like a black hole the power of the emptiness has the ability to pull a person towards complete destruction, so Hashem tempered it to give a person the ability to resist the force. עלה במחשבה לברוא את העולם במדת הדין וראה שאינו מתקיים...

Boundaries: 1

From a state on infinite holy omnipresence through a state of continuous constriction there arose a place that was empty and devoid of holiness. It was through the creation of boundaries that it became possible for a void to exist.
In a state of complete unboundedness everything is full of Hashem's presence. The creation of boundaries by definition means that the presence is bound to a limited area and there is an area in which it is not present. This is the void.

Hashem Elokim: 3

The line connecting and unifying the disparate and oppositional circles is a manifestation of the name יקוק which represents the singular will of Hashem that underlies all of Creation. (שמו בגימטריאא רצון) The panoply of powers represented by the circles, each expandable in myriad directions and to infinite depth is represented by the name אלוקים, which represents the manifestation of Hashem's presence in a multitude of ways.
In the ultimate truth, the name representing unity is the one that describes Hashem, but for the creation of existence, the name representing more than one is needed. Both of these approaches, which seem to be mutually contradictory, are needed.
Indeed, there is no contradiction. יקוק represents the inner truth of existence, while אלוקים, represents how it appears to us within Creation.