R. Tzadok Ha-Kohen on Purim: Minimal Excess

This is the aspect of Purim, that they did not accept upon themselves the prohibition of  melacha (TB. Megillah 5b). For in truth, the nullification of melacha is from the perspective of God who has no need for effort (his’tadlut), and it is only applicable to the perspective of God and the sanctity of the Sabbath which is permanent and enduring.

This is not the case when it comes to yom tov whose sanctity depends on the Jewish people and as such remains dependent on effort. The nullification of melacha, however, is only because on yom tov there is an additional sanctity that is created by the Jewish peoples sanctification. Furthermore, the sanctity of yom tov is rooted in the sanctity of the Sabbath , meaning, the sanctity of God that is the source of all from which all draw their strength. This surplus sanctity of yom tov then becomes an aspect of “permanent and enduring”.

On Purim however, there is no addition, rather, there is a disclosure of a light that negates the need for addition, for when one is connected to essence there is no surplus. This is the reason that while all  yamim tovim stand to be nullified in the future, Purim will never be nullified; for every yom tov  is rooted in the miracle and salvation that creates an addition, while in the future God will be “the light of days” negating all novelty and addition. Purim, however, is rooted in this very light.

In truth, there is no addition. It is only from the perspective of this worldliness that addition exists. There is only this additional insight which reveals that there is no addition whatsoever.

(Resisei Leila, 32:3)