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Holy Zohar text. Daily Zohar -548.

Hebrew translation:

וְאוֹתָן הַתְּמוּרוֹת הֵן סוֹד הַיִּבּוּם, שֶׁנֶּאֱמַר בָּהּ בַּיְבָמָה עַל הַגְּאֻלָּה וְעַל הַתְּמוּרָה, לְקַיֵּם כָּל דָּבָר, שָׁלַף אִישׁ נַעֲלוֹ וְנָתַן לְרֵעֵהוּ, בְּאוֹתָהּ נַעַל שֶׁנָּתַן לְרֵעֵהוּ יֵשׁ תְּמוּרָה וְשִׁנּוּי רָצוֹן, וְשָׁם צָרִיךְ שִׁנּוּי מָקוֹם וְשִׁנּוּי הַשֵּׁם וְשִׁנּוּי מַעֲשֶׂה לְקַיֵּם כָּל דָּבָר, הַנַּעַל הוּא הַגּוּף.
וְלָמָּה בַּחֲלִיצַת נַעַל שֶׁנָּתַן לְרֵעֵהוּ יֵשׁ תְּמוּרָה וְשִׁנּוּי? אָמַר זָקֵן אֶחָד: רַבִּי רַבִּי, אַל תֹּאמַר כָּךְ, אֶלָּא לָמָּה חֲלִיצָה בְנַעַל? אֶלָּא הִיא הַקְּלִפָּה לְהִסְתַּתֵּר בָּהּ לְהִנָּצֵל מִמֶּנּוּ, וְלֹא נוֹדַע אֶל הַמְקַטְרְגִים שֶׁלּוֹ, וּבַחֲלִיצָה שֶׁל נַעַל חוֹלֵץ לוֹ י”ה, וּמִשּׁוּם זֶה שָׁלַף אִישׁ נַעֲלוֹ וְנָתַן לְרֵעֵהוּ, נַעַל ו’, גַּן נָעֻל, שֶׁהוּא בֶּן י”ה, לְהִכָּנֵס בֵּין ו”ה, וְזֶהוּ חָלַץ י”ה. 

Tikkun 26 – 6

Ruth 4:7
“וְזֹאת לְפָנִים בְּיִשְׂרָאֵל עַל-הַגְּאֻלָּה וְעַל-הַתְּמוּרָה, לְקַיֵּם כָּל-דָּבָר, שָׁלַף אִישׁ נַעֲלוֹ, וְנָתַן לְרֵעֵהוּ; וְזֹאת הַתְּעוּדָה, בְּיִשְׂרָאֵל ”
“Now this was the custom in former time in Israel about the Redemption and about the exchange, to keep in existence all things: a man drew off his shoe, and gave it to his neighbor; and this was the attestation in Israel.- ”

The Torah instructs us NOT to marry the ex-wife of a brother but Levirate marriage is a great Mitzvah. This process is called יבום (Yibum). If a man dies, leaving a widow without children, his brother should come to the woman, have sex together to impregnate her and with that action they become married to each other. This process of connecting the woman as Malchut to the Man as Zeir Anpin is called גאולה, “redemption” and the man is called גואל, “redeemer”.

The sages made a requirement to go through the ceremony of Kidushin before the brother and the widow can come together. This was done to remove the negativity of selfish desires that can easily get attached to this holy process.

If the brother doesn’t want to connect and marry his brother’s widow, they must go through a process called חֲלִיצָה, meaning ‘release from limits’. In it the woman draws off the shoe of her in-law along with other spiritual actions.

Shoe is נעל, with numerical value 150, same as YH יה times 10. With the letter Vav we get נעול, which means ‘locked’. The word for ‘release from’, חֲלִיצָה, is constructed from חלצ, ‘release’, ‘rescue’ and יה, YH.

When the widow draws off the shoe she releases the lock from Malchut to the supernal Father (Chokmah) and Mother (Binah) and frees the child, Zeir Anpin.
When the couple were married the light was ready with the fulfillment. After the husband dies, the potential light for bringing a child to the world must be fulfilled, otherwise it will turn to judgment and negativity.

The widow needs to have the brother channel that light to fulfill the vessel or alternatively release it.

The secret the Zohar reveals here is that the light becomes available when the process is initiated. All we need to do is to follow through all the way to fulfillment.