The joys (and hangovers) of Purim are still in the air when the biblical portion of Ki Tisa arrives to teach us one of the most important lessons of Jewish theology: Why is the divine face so often hidden? Why does the world in general and life in particular so often seem to lack God's presence? After all, Purim features the concealment of God, which is why His name is absent from the Scroll of Esther. And although Persia's Jewish community avoids destruction, it must nevertheless undergo a costly battle and, at the end of the day, Esther remains married to a gentile despot and the Jews are still in that despot's service. No wonder we must drink to induce feelings of gaiety! But why must we endure exile and angst, persecution and pogrom as the built-in cost of mere survival? "My God, why hast Thou forsaken us?" Our portion provides the reason. The nation has sinned by worshiping the materialistic, hedonistic golden calf. Moses wishes total absolution for his people and, what's more, desires God's "face" to be with them constantly (Exodus 33:15) - that God's goodness and compassion be manifest at all times. God explains that no mortal may see His face and live; that God can only lead from behind a veil (Exodus 33:23). Indeed, the Almighty even explains that His hiddenness is a blessing and not a curse: "I shall send before you an agent [or messenger, or angel, or national leaders] and [in this manner] I shall banish the Canaanites; but I shall not arise in your midst because you are a stiff-necked people, lest I consume you on the way... And the Lord said to Moses: 'Say to the children of Israel, you are a stiff-necked nation; if for one moment I were to arise in your midst, I would destroy you...'" (Exodus 33:2-5). God's open manifestation in human affairs would be a double-edged sword. Since a real-time, instant-to-instant divine presence implies the immediate reward of the righteous and the immediate punishment of the evil, the Israelites might have found themselves totally eliminated before their history got under way. The sin of the golden calf alone, for example, would have brought total and immediate annihilation if God had operated in an open and direct fashion. And so God established a special relationship - a covenant - with our nation, which He shall lead "from behind" to ensure that we can lead the world from "in front" - by example - until it becomes a place fit for His presence to be manifest (Exodus 34:10 ff., and 25:8). In the meantime, God will give all of humanity, Israel included, an opportunity to repent and improve, to experience triumphs and tragedies, privileges and punishments, until the time of redemption. Hence God tells Moses that he must leave the supernal heights from where he can hear His voice directly and descend to the Israelites wallowing around the golden calf. Because the entire nation must be uplifted, purged and purified (Exodus 32:7, B.T. Brachot 32a). God made a covenant with an entire nation, and until that whole nation - God's messenger - is entirely uplifted and healed, His name will not be complete and manifest in the world. From this perspective, Purim takes on a new dimension. Yes, God was completely hidden in the assimilating and fragmented Jewish nation living in Persia toward the end of the sixth century BCE. Esther's very name reflects God's manifest absence (hester, hidden), as this woman of noble Jewish ancestry enters the Persian king's harem. There were totally assimilated Jews who patriotically identified the Persian palace with the desert sanctuary and Holy Temple (Esther 1:5, ff.), and totally unassimilated Jews who wept each midnight over tikkun hatzot (a plea for restoration of the Temple); there were partially assimilated Jews who reveled together with the Persians but ate only fish, and other partially assimilated Jews who showed up to avoid punishment, but didn't touch a morsel of food. Was it not Haman who described the Jews as "scattered and separated" (Esther 3:8)? And it is Esther, although she tries at first to convince Mordechai to stop his demonstrations, who eventually understands that even partial victory can only be won if the Jewish community in the capital is completely united under God. Hence, while Mordechai only demands that Esther plead before King Ahasuerus, Esther demands that first "Mordechai must go and assemble all the Jews of Shushan together to declare a period of fasting and prayer. Do not eat or drink anything for three days and nights. My servant girls and I will do the same. After that, I shall go to the king... and if I am destroyed, I shall be destroyed..." (Esther 4:15, 16). And so our method of celebrating Purim expresses the coalescence of our communal ties: charity to the poor, gifts to friends, communal meals and reading the Scroll of Esther in communal gatherings. The more united our nation becomes, the more united and manifest God's name will be, until that time when we witness the unification of the world under the one God of justice, compassion and peace. The writer is the founder and chancellor of Ohr Torah Stone Colleges and Graduate Programs, and chief rabbi of Efrat.