Seeing beyond the Concealment — Eruvin 65a
תלמוד בבלי מסכת עירובין דף סה/ב
אמר רבי אילעאי בשלשה דברים אדם ניכר בכוסו ובכיסו ובכעסו ואמרי ליה אף בשחקו:
If you remove the vav from koso; the yud from kiso and the ayin from ka'aso, all three words spell כס — kes.
The word kes appears at the end of Parashas BeShalach:
ספר שמות פרק יז
טז) ויאמר כי יד על כס י-ה מלחמה לה' בעמלק מדר דר
As Rashi notes there, Chazal state that neither the throne of Hashem will be complete (the כס is missing the final א nor will His Name be complete (the last two letters ו-ה are missing) until Amalek is eradicated.
כס would seem to mean "like [כ' הדמיון] a samech." A samech is the only letter in original Lashon HaKodesh (see Shabbos 104a) that is completely closed. It therefore represents concealment - a lid, as in מכסה or כיסוי. A chair may be a כסא because while one is sitting, it covers on (also, the seat of a chair is like a ס while its back is like a כ.
Without the א, the entire world is כ-ס - like concealment. What is missing is the Yechido shel Olam.
What is unique about these three things - they all have letters that break through the concealment - come between the kaf and the samech. The sum total of all those three letters - yud, ayin, vav - is again Kos (86) - but also the shem Elokim (86) - the name that is manifest even in the concealment (86 is also the gimatria of הטבע — nature — and which is therefore
the ו' החיבור — the connecting line that pierces through the concealment.
The ultimate Geulah will be when that connection allows us to perceive Hashem in all aspects of our existence — in our day to day lives (our pockets), in our anger and in our happiness (our cups of joy). Then, after all of the כס is at an end, we will perceive how all was really connected to, and came from, the א.