Musar su Deuteronomio 25:19

G–d responded: "Indeed My Presence will go." To the request that this should occur already at this time, G–d said this will occur at a time והניחותי לך, "when I will will grant rest, i.e. in the land of Israel itself, not on the journey." A parallel meaning of the word והניחותי may be found in Deut. 25,19, in conjunction with the duty to wipe out Amalek after G–d has given the Jewish people rest, i.e. בהניח from all their enemies becomes operative. You might ask that if G–d had already told Moses that His Presence in the form of the Ineffable Name would be revealed once the Jewish people were in the land of Israel, what would have been the advantage if Moses had been allowed to bring the Jewish people to the land of Israel? In either event there would be a manifestation of the Ineffable Name in the land of Israel? Under the leadership of the angel who accompanied Joshua G–d's Presence as the Ineffable Name became manifest only within the precincts of the Holy Temple. Had Moses been allowed to bring the Jewish people into the Holy Land, such a presence of the Ineffable Name would have been manifest throughout the Holy Land, not only within the precincts of the Holy Temple.

In this connection I find the words of Rabbi Yitzchak Arama, the author of עקדת יצחק, most astonishing. The author of this book [chapter 90, see my translation. Ed.] questions how the Torah can command us to remember something at all; after all, man is subject to lapses of memory, and therefore such a commandment is beyond his control to observe! How can the Torah command us to perform acts beyond our control? Torah precepts involving vision do not apply to the blind because they cannot see, neither do Torah precepts involving hearing apply to the deaf since they cannot hear! The same rule should apply to precepts involving memory. Rabbi Arama answers this question saying that every remembrance has been preceded by an actual happening. It is the happening which triggers one's memory, and therefore the Torah is entitled to command us to use our memory. He quotes as an example the remembrance of the Sabbath legislation in the Kiddush. The mere fact that one observes the commandment of שמירת שבת, abstains from work, etc., acts as a memory jogger. It is therefore not true to say that the Torah commands only our memory. When we put on the phylacteries, that very act helps us to remember what the phylacteries stand for, as demanded by the Torah (Deut. 6,8); the same is true when we wear the ציצית, another commandment which the Torah has linked to memory (Numbers 15,39-40). The sages of the Great Assembly acted in consonance with this principle when they wanted to insure that the miracle which occurred in the days of Mordechai and Esther should be commemorated for all times. Since the Torah had not fixed a specific day for remembering Amalek, they decided to anchor this remembrance by some easily recognisable act and they instituted the reading of פרשת זכור in conjunction with the holiday of Purim. As long as the commandment was not connected with the anniversary of an anti-Jewish act committed by a descendant of Amalek, the commandment itself was in danger of being forgotten. According to the explanation by the Baal Akeydah the question is why the sages of the Great Assembly did not arrange to have the reading of פרשת זכור after Purim, after we had all remembered what the evil Haman had planned?

In fact, Queen Esther would have liked to have evoked pure mercy, for the Divine name in its simple form [i.e., and not as an acronym] and in proper sequence is a Name of mercy. But if Esther had not mentioned this Name in an acronym of initial letters she would have been unable to defeat Haman. In her wisdom she knew that she must incorporate a small amount of judgment as well as mercy in order that this judgement would take revenge upon Haman, oppressor of the Jews. After this it is stated, “For he saw that the evil was concluded against him from the king” — Ki ra’ah kY chalsaH eilaV hara’aH mei’eis hamelech (Esther 7:7), the “king” being an allusion to the King of Universe. Note that the Divine name appears here in proper sequence indicating mercy for Israel. Nevertheless, it appears as an acronym of final letters to hint at the judgment and destruction that was to befall Haman and his sons. From here we can see the extent of the wicked Haman’s evil intentions towards Israel. In him was fulfilled the verse, “He excavated a pit and dug it out” (Tehillim 7:16). That is, he was ensnared by the very trap that he laid. Therefore the Torah has commanded us to wipe out the name of Amaleik and his seed and the seed of his seed. Thus the Sages have taught (Sifri, Devarim 25:19; Mechilta DeRashbi, Shemos 17:14) that one must blot out the name of Amaleik even from upon the trees and stones. This is the source of the custom — and the customs of Israel are Torah — to bang upon hearing Haman’s name, in order to wipe out his name and that of Amaleik. All the authorities, both earlier and later, have written that one must not abolish this custom.