Source and decoding - Rosh Hashanah 16b
שְׁלֹשָׁה סְפָרִים נִפְתָּחִין בְּרֹאשׁ הַשָּׁנָה, אֶחָד שֶׁל רְשָׁעִים גְּמוּרִין, וְאֶחָד שֶׁל צַדִּיקִים גְּמוּרִין, וְאֶחָד שֶׁל בֵּינוֹנִיִּים.
Three books are opened on Rosh Hashanah: of the completely wicked, the completely righteous and the intermediate.
Three books are opened on Rosh Hashanah: of the completely wicked, the completely righteous and the intermediate. The completely righteous are immediately written and sealed for life, the wicked for death, and the intermediate are suspended from Rosh Hashanah to Yom Kippur: if they merit - written for life; if not - for death.