Before midnight the left column is in control and Malchut is in a state of darkness without the light of Chassadim. At midnight the Light of the Endless begins to reveal itself and unifies the Left with the Right to form the Central column. Malchut is awakened to the Central column and able to connect to the Light of the Endless.
By morning the Light of the Endless, “the Holy One, Blessed be He”, reaches Malchut with a thread of silver that is the Light of Chokmah in the vessel of Chessed.
“וַיְהִי כִרְאוֹת הַמֶּלֶךְ אֶת-אֶסְתֵּר הַמַּלְכָּה, עֹמֶדֶת בֶּחָצֵר–נָשְׂאָה חֵן, בְּעֵינָיו; וַיּוֹשֶׁט הַמֶּלֶךְ לְאֶסְתֵּר, אֶת-שַׁרְבִיט הַזָּהָב אֲשֶׁר בְּיָדוֹ, וַתִּקְרַב אֶסְתֵּר, וַתִּגַּע בְּרֹאשׁ הַשַּׁרְבִיט”
“When the king saw Esther the queen standing in the court, she obtained favor in his sight; and the king extended to Esther the golden scepter which was in his hand. So Esther came near and touched the top of the scepter.”
This revelation of light in the morning is the aspect of the King giving the queen the royal scepter, allowing her to use his forces as she see proper. The Zohar emphasis that all of those who connect with the queen benefit from that power.
The infinite wisdom of the Creator provided us with a system to study and use its tools. This gives us ability to connect and draw great lights that benefit us during the day and during our entire life.
After midnight we can tap to the root of the light of Chessed. Many do this connection every day. They go to sleep early and wake up between midnight and first light so they can draw this light of Chessed.
After Joshua takes the leadership role from Moses, God gave him important advice.
“לֹא-יָמוּשׁ סֵפֶר הַתּוֹרָה הַזֶּה מִפִּיךָ, וְהָגִיתָ בּוֹ יוֹמָם וָלַיְלָה, לְמַעַן תִּשְׁמֹר לַעֲשׂוֹת, כְּכָל-הַכָּתוּב בּוֹ: כִּי-אָז תַּצְלִיחַ אֶת-דְּרָכֶךָ, וְאָז תַּשְׂכִּיל”
“”This book of Torah shall not depart from your mouth, but you shall meditate on it day and night, so that you may be careful to do according to all that is written in it; for then you will make your way prosperous, and then you will have success.”
In Zohar Balak #314 the Zohar praises those who study the Torah day and night.
“אַשְׁרֵי הָאִישׁ– אֲשֶׁר לֹא הָלַךְ, בַּעֲצַת רְשָׁעִים;
וּבְדֶרֶךְ חַטָּאִים, לֹא עָמָד, וּבְמוֹשַׁב לֵצִים, לֹא יָשָׁב.”
“כִּי אִם בְּתוֹרַת יְהוָה, חֶפְצוֹ; וּבְתוֹרָתוֹ יֶהְגֶּה, יוֹמָם וָלָיְלָה.”
“Blessed is the man who walks not in the counsel of the wicked, nor stands in the way of sinners, nor sits in the seat of scoffers;”
“But his delight is in the Torah of YHVH, And in His Torah he meditates day and night.”
For more on this subject read here: http://www.chabad.org/kabbalah/article_cdo/aid/1321935/jewish/Up-at-Midnight.htm