The entry of the light into the vessels and its exit are the root of the governmental order of this world in a state of damage and repair.
The cycle's entry-and-exit of light — the breaking and the repair, the descent and the return — is the root of the governmental order. Nothing is in vain; exact measure — neither less nor more.
Op. 50 closes the World of Nekudim unit with a structural-philosophical conclusion. The breaking and repair are not events that happened to the cosmos; they are the cosmic government's operational form. Every later cycle of damage-and-repair (every soul's exile and return; every cosmic descent and ascent; every weekday and Shabbat) is a microcosm of the Op. 50 entry-and-exit pattern.
The striking claim: nothing is in vain. Every spark that fell, every soul that lost itself in the husks, every moment of cosmic darkness — none of this is waste. The entry-and-exit of light is exactly the operational architecture the cycle requires. The breaking produced something the cosmic plan needed (the realm of deficiency, the ground of service); the repair will produce something the plan also needs (the demonstration that deficiency was always temporary).
The phrase exact measure echoes Op. 14's exactly required doctrine and Op. 68's every part exactly calibrated. The amount of light that entered, the amount that exited, the timing of each — neither less nor more. The cosmic plan has the structural precision of a finely calibrated instrument.
Revealed vs. occluded lights is also worth noting. After the breaking-and-repair, the cosmic structures contain both revealed lights (the operational ones we can see) and occluded lights (the concealed ones whose action is real but invisible). This duality runs through the rest of the book: the concealed governmental order of Op. 78–84 is its sharpest later form.
Op. 53 will close the States of the First Three Sefirot unit by stating the order of the repair. Op. 81 will distinguish the concealed and revealed governmental orders. The closing chapters will operationalise the exact measure and nothing is in vain doctrines in the eight-stage Coupling order of Op. 138.