Spirit of the Law: Purim 141:6

(Kitzur Shulchan Aruch 141:6) “On Purim…one says Al HaNissim.”
Reb Nosson, zt”l, explains that the “Al HaNissim” prayer was instituted because we overcame the kingdom of Yavan and the evil Haman, who were jealous of us and wanted to keep us from serving Hashem. Haman didn’t even want any Jew to be left alive! However, Hashem in His great mercy didn’t abandon us. He turned our grief and anguish into joy. Not only did they fail abysmally, but we gained two holy festival—Chanukah and Purim—which have sustained us throughout our long exile. We see, then, that their very attempt to destroy us has actually been the means through which we have gained the strength we need to survive until the redemption. The events that led up to our deliverance have made us worthy of receiving new and powerful spiritual illuminations and new mitzvos: the lighting of the menorah, recitation of Hallel, and the special Torah readings on Chanukah; and the reading of the megillah, sending of mishloach manos, contributions to the poor, and the festival meal and drinking on Purim.
The descent turned into an ascent—this is the character of Chanukah and Purim, and it can also be true for everyone, all the time. Every day, and at every moment, Hashem is orchestrating events in the most miraculous way to prevent us from falling completely. On the contrary, He turns all of our falls into ascents if we are only willing and try our best to begin again. This is the essence of doing teshuvah our of love—through which all of our sins are transformed into merits. This is how we can rise ever higher in our service of Hashem!