Ezra 6:19 Midrash

וַיַּעֲשׂ֥וּ בְנֵי־הַגּוֹלָ֖ה אֶת־הַפָּ֑סַח בְּאַרְבָּעָ֥ה עָשָׂ֖ר לַחֹ֥דֶשׁ הָרִאשֽׁוֹן׃

And the children of the captivity kept the passover upon the fourteenth day of the first month.

Read midrashic interpretation of Ezra 6:19: and classical rabbinic exegesis.