דבר אל בני ישראל, מועדי ה'. עֲשֵׂה מוֹעֲדוֹת שֶׁיִּהְיוּ יִשְֹרָאֵל מְלֻמָּדִין בָּהֶם, שֶׁמְּעַבְּרִים אֶת הַשָּׁנָה עַל גָּלֻיּוֹת שֶׁנֶּעֶקְרוּ מִמְּקוֹמָן לַעֲלוֹת לָרֶגֶל וַעֲדַיִן לֹא הִגִּיעוּ לִירוּשָׁלַיִם (ספרא): 'דבר אל בני ישראל, מועדי ה SPEAK UNTO THE CHILDREN OF ISRAEL [AND DECLARE UNTO THEM] THE APPOINTED FESTIVALS OF THE LORD — This means, Regulate the festive seasons in such a manner that all Israel should become practised in them (their observance). Hence we derive the law that they (the Sanhedrin) proclaim a leap-year (i. e. intercalate a second Adar) for the sake of those living in the diaspora who have already left their homes in order to go up for the festival but have not yet arrived in Jerusalem (Sifra, Emor, Section 9 1; cf. Sanhedrin 11a).