Chasidut for Pesachim 3:15

This corresponds to (Pesachim 2a) "On the evening [אוֹר] of the fourteenth of the month of Nisan, one searches for leavened bread in his home by candlelight", and the Tanna read אוֹר as evening, employing a euphemism, etc. The essence of the search for Chametz and its burning is the aspect of elimination, the aspect of the nature from the world, which corresponds to Chametz, as explained above. When nature is nullified and providence is revealed, this is the aspect of nullification of the darkness and the night, as explained above. They are the aspect of the power of the exile which is drawn from the aspect of knowledge of natural science, as explained above. For when His Blessed Divine Providence is revealed in the world, then there is no darkness there at all. The essence of light is Hashem Yisbarach, so to speak, as explained above. Then, night is illuminated like the day, etc. As it is written (Psalms 139:12) "Even darkness will not obscure [anything] from You, and the night will light up like day", as it will be in the future, as it is written (Zechariah 14:7) "and it shall come to pass that at eventide it shall be light", as we request (Passover Haggadah ) "illuminate like the light of the day, the darkness of the night". The essence of the darkness of night is from the knowledge of natural science, which is the essence of darkness, while faith in divine providence is the essence of light, as explained above. Therefore, the night of searching for Chametz nullifies nature, as the Tanna was using a euphemism regarding the nullification of nature, which is the aspect of Chametz which was searched for on that night. By this, night corresponds to day, the aspect of (Psalms 139:12) "and the night will light up like day", etc., as explained above. And therefore the Tanna called that night 'light', אוֹר.