Rosh Hashanah (רֹאשׁ הַשָּׁנָה) equals 861, which is also the value of the verse (Psalms 119:91), “They stand today before Your judgments, for all are Your servants” (לְמִשְׁפָּטֶיךָ עָמְדוּ הַיּוֹם כִּי הַכֹּל עֲבָדֶיךָ). This is the only verse in the entire Tanach whose value is 861.
On Rosh Hashanah everyone does teshuvah and returns to God, even Datan and Aviram, who were known for their rebellion against Moshe Rabbeinu, for indeed, “Datan and Aviram” (דָּתָן וַאֲבִירָם) equal “teshuvah” (תְּשׁוּבָה)! Datan and Aviram are particularly connected with parashat Nitzavim (נִצָּבִים) as the verse reads (Numbers 16:27), “Datan and Aviram came out and they stood” (וְדָתָן וַאֲבִירָם יָצְאוּ נִצָּבִים).
Rosh Hashanah is known in the Torah as, “A day of Teru’ah [of blasting the shofar]” (יוֹם תְּרוּעָה), a phrase whose value is 737, which is also the value of “with all of your heart, with all of your soul, and with all your means” (בְּכָל לְבָבְךָ וּבְכָל נַפְשְׁךָ וּבְכָל מְאֹדֶךָ).
In the Haftarah of the second day of Rosh Hashanah we read the verse that the Lubavitcher Rebbe particularly loved (Jeremiah 31:8), “Behold, I am bringing them from the northland, I will gather them from the ends of the earth; among them the blind and the lame, those with child and those in labor together; a vast throng they shall return here” (הִנְנִי מֵבִיא אוֹתָם מֵאֶרֶץ צָפוֹן וְקִבַּצְתִּים מִיַּרְכְּתֵי אָרֶץ בָּם עִוֵּר וּפִסֵּחַ הָרָה וְיֹלֶדֶת יַחְדָּו קָהָל גָּדוֹל יָשׁוּבוּ הֵנָּה). This verse is full of many beautiful and important numerical phenomena.
The value of the first 6 words (הִנְנִי מֵבִיא אוֹתָם מֵאֶרֶץ צָפוֹן וְקִבַּצְתִּים) is 1820, the number of instances God’s essential Name, Havayah appears in the Pentateuch.
The value of “the blind [and] the lame” (עִוֵּר פִסֵּחַ) is equal to “Mashiach ben David” (מָשִׁיחַ בֶּן דָּוִד). Just “blind” (עִוֵּר) equals “eternal life” (חַיִּים נִצְחִיִּים) and “lame” (פִסֵּחַ) equals “eternity” (נֶצַח).
“The blind and the lame, those with child and those in labor together” (עִוֵּר וּפִסֵּחַ הָרָה וְיֹלֶדֶת יַחְדָּו) equals 1118, the value of the first verse of the Shema (שְׁמַע יִשְׂרָאֵל י-הוה אֱ-לֹהֵינוּ י-הוה אֶחָד), the quintessential statement of God’s unity.