שֵׁ֣שֶׁת יָמִים֮ תֵּעָשֶׂ֣ה מְלָאכָה֒ וּבַיּ֣וֹם הַשְּׁבִיעִ֗י שַׁבַּ֤ת שַׁבָּתוֹן֙ מִקְרָא־קֹ֔דֶשׁ כָּל־מְלָאכָ֖ה לֹ֣א תַעֲשׂ֑וּ שַׁבָּ֥ת הִוא֙ לַֽיהוָ֔ה בְּכֹ֖ל מֽוֹשְׁבֹתֵיכֶֽם׃ (פ)
六日要做工，但第七日是完全安息的安息日，是聖會；任何工作你們都不可做。在你們一切的住處，這是歸給永恆者的安息日。
Sifra
1) Above (Vayikra 23:2), intercalation of the year is being spoken of, and here (Vayikra 22:4) sanctification of the month is being spoken of. If (the moon) were seen clearly, or witnesses came and testified (to that effect) before them (beth-din), and they were unable to proclaim "It is intercalated until it became dark — whence is it derived that it is intercalated? From "which you shall call (them) in their times." If you called them, they are My festivals. If not, they are not My festivals.
Sifra
2) If they sanctified it (erroneously) without witnesses, or if witnesses came and testified and were found to be scheming witnesses, whence is it derived that it is sanctified? From which you shall call (them) in their times." If you called them, they are My festivals. If not, they are not My festivals.
Sifra
3) If they sanctified it perforce or unwittingly or mistakenly, whence is it derived that it is (nevertheless) sanctified? From which you shall call (them) in their times. "them" — even mistakenly; them — even perforce.