Deuteronomy 21: 23
“לֹא-תָלִין נִבְלָתוֹ עַל-הָעֵץ, כִּי-קָבוֹר תִּקְבְּרֶנּוּ בַּיּוֹם הַהוּא–כִּי-קִלְלַת אֱלֹהִים, תָּלוּי; וְלֹא תְטַמֵּא, אֶת-אַדְמָתְךָ, אֲשֶׁר יְהוָה אֱלֹהֶיךָ, נֹתֵן לְךָ נַחֲלָה. ”
“his corpse shall not hang all night on the tree, but you shall surely bury him on the same day (for he who is hanged is accursed of God), so that you do not defile your land which YHVH your God gives you as an inheritance.”
The Torah tells us that we should not leave the body on the tree for long, it should be buried before the day passes, meaning before sundown.
“כִּי הָאָדָם עֵץ הַשָּׂדֶה” “for the man is the tree of the field”
Man was created in God’s image, which is the Tree of Life. When the soul leaves the body, it is left only with the temporary aspect of its existence and immediately goes into the decay process. The body that was previously gathered from the matter of this world is no longer in use by the soul. The body is initially formed in the womb, grows, leaves the womb and recycles its existence many times on the physical level to keep the soul drawing life energy into it. Now, without the soul it breaks down to the basic elements all the way down to basic atoms.
The decay process is the aspect of Judgment and should be ‘grounded’. Nature and the living people are the aspect of the Tree of Life and we should distance ourselves from the negativity of the dead.
While the lifeless body is still above ground the soul suffers from great pain. It can not go up for the judgment that determines the cleansing and the new reincarnation process. Some souls need to have immediate reincarnation and if not buried immediately they may lose important correction cycle.
When the soul ascends, it receives new spiritual garments, but only after the first body that was its garment in this world is buried.