לזכות א.ב.ה.מ
Says the Rambam [Melachim 6-6]:
"עמון ומואב אין שולחין להם לשלום שנאמר לא תדרוש שלומם וטובתם כל ימיך. אמרו חכמים לפי שנאמר וקראת אליה לשלום יכול עמון ומואב? כן תלמוד לומר "לא תדרוש שלומם וטובתם", לפי שנאמר "עמך ישב בקרבך בטוב לו לא תוננו" יכול עמון ומואב כן? תלמוד לומר "וטובתם" ואע"פ שאין שואלים בשלומם אם השלימו מעצמם תחלה מקבלין אותן":
"No offer of a peaceful settlement should be made to Ammon and Moav, as Devarim 23:7 states: 'Do not seek their peace and welfare for all your days.' Our Sages declared: Although it is written: 'Offer a peaceful settlement,' does this apply to Ammon and Moab? The Torah states: 'Do not seek their peace and welfare.'
Although it is written Devarim 23:17: 'He must be allowed to live alongside you in you midst,' does this apply to Ammon and Moav? No, the Torah also forbids 'their welfare.'
Even though we should not offer them a peaceful settlement, if they sue for peace themselves, we may accept their offer."
What is the source of the latter assertion of the Rambam "... if they sue for peace themselves, we may accept their offer"?
The Minchas Chinuch [562] writes that this is the Rambam's independent סברא based on the language of the Sifre that only forbade קריאה לשלום - actively calling out for peace, implying that if they want to make peace on their own, it is permitted to accept their offer. The question is, that if it is dictated by simple logic - סברא פשוטה - then why did the Rambam have to tell us? And if it is his own chidush then why doesn't he use the language of "יראה לי", as is his wont. It would seem that it is in fact a סברא פשוטה but the Rambam is coming to preclude another opinion. What opinion is that?
In the Hagaos Maimoniyos here he writes:
כ' רא"מ בד"א בדרישת שלום אבל בתשלומי שלום מותר, כגון אם עשו עמך חסד מותר לפקדם לשלום, שנאמר (שמואל ב' פ"י א') וימת מלך בני עמון וימלוך חנון בנו תחתיו, ויאמר דוד אעשה חסד עם חנון כאשר עשה אביו עמדי חסד, וישלח דוד לנחמו, וכן ס"ח משמו
The רא"מ writes that only seeking out peace is forbidden but to REPAY with peace is permitted. Such as in a case where they performed a chesed for us it is permitted to repay them with chesed, as it says [Shmuel 2/10-1] "And it came to pass after this, that the king of the children of Ammon died, and Chanun his son reigned in his stead. And Dovid said: "I shall show kindness to Chanun the son of Nachash, just as his father showed me kindness. And Dovid sent to comfort him through his servants, for his father. And Dovid's servants came into the land of the children of Ammon". So wrote the Sma"g [ל"ת רכ"ח עיי"ש].
The Kesef Mishna wrote:
ויש לתמוה ע"ז, שאמרו חז"ל במדרש שלא כהוגן עשה דוד בזה, ע"כ.
This is a wonder because Chazal were critical of Dovid for his actions?!
He is referring to the Medrash Rabba and Tanchuma in Pinchas:
את מוצא במי שבא עליהם במדת רחמים לסוף בא לידי בזיון ומלחמות, ואיזה זה דוד, ויאמר דוד אעשה חסד וגו', א"ל הקב"ה אתה תעבור על דברי, אני כתבתי לא תדרוש שלומם וטובתם ואתה עושה עמהם גמ"ח, אל תהי צדיק הרבה, שלא יהא אדם מוותר על התורה וכו'.
This Medrash clearly indicates that Dovid was mistaken and one shouldn't be "frummer" than the Torah and make peace with the Ammonites.
The pasuk says further:
וַיֹּאמְרוּ֩ שָׂרֵ֨י בְנֵֽי־עַמּ֜וֹן אֶל־חָנ֣וּן אֲדֹֽנֵיהֶ֗ם הַֽמְכַבֵּ֨ד דָּוִ֚ד אֶת־אָבִ֙יךָ֙ בְּעֵינֶ֔יךָ כִּֽי־שָׁלַ֥ח לְךָ֖ מְנַֽחֲמִ֑ים הֲ֠לוֹא בַּעֲב֞וּר חֲקֹ֚ר אֶת־הָעִיר֙ וּלְרַגְּלָ֣הּ וּלְהָפְכָ֔הּ שָׁלַ֥ח דָּוִ֛ד אֶת־עֲבָדָ֖יו אֵלֶֽיךָ:
And the princes of the children of Ammon said to Chanun their lord: "Do you think that David honors your father that he sent you comforters? Is it not in order to investigate the city and to spy it out, and to search it that David has sent his servants to you?"
The Medrash comments:
הנראה בעיניך שדוד מכבד את אביך, הם מוזהרים לא תדרוש שלומם והוא ידרוש שלומך
Do you think that Dovid honors your father? The Jews are commanded not to seek out your peace and he is seeking out your peace?! It must be that they are investigating the city and spying it out!
So how odd that the רא"מ should use a pasuk as a source that one may make peace when we are repaying a debt when it is in fact a proof AGAINST?!
The Ohr Sameach takes a stab at explaining the רא"מ:
"דאם עשה עמו חסד בעצמו ודאי מותר, אלא ששם עשה אביו עמו חסד, ובזה סבר דוד דגם בכה"ג שרי, ואינו כן, אבל כ"ז משום דבעשה חסד עמו עכ"פ שרי".
Avers the O.S. - If the son himself had done a chesed for Dovid it would have been OK. Dovid's mistake was that he extended the היתר to when his father did chesed. That is how the רא"מ derived that if one does a personal chesed for you then it is permitted to repay in kind.
But this is שווער צו זאגן ["a questionable claim" in Sanskrit]: This is not a דרשה from a pasuk but logic. The pasuk doesn't refer to a case when you owe them a favor. Dovid obviously felt that the היתר to make peace applies to repaying the child for the chesed of the father as well. So what was his mistake exactly? It would seem more compelling that he made a mistake thinking that repayment of a favor at all is permitted. So נאך אמאל ["again" in French]: How can the רא"מ use this source as a proof when in fact it is a proof against??!
The Ramban Al Hatorah there in Parshas Ki Teiztei quotes the command of Elisha to wage war against Moav and the Medrash thereon:
והכיתם את כל עיר מבצר, וכל עיר מבחר וכל עץ טוב הפילו, וכל מעייני מים תסתמו, וכל החלקה הטובה תכאבו באבנים, עיי"ש אמר לו הכ' אומר ולא תשחית את עצה ואתה אומר כן, אמר להם על כל האומות צוה וזו קלה ובזויה היא, שנאמר ונקל זאת וכו', שנאמר לא תדרוש שלומם וטובתם אלו אילנות טובות וכו', ע"כ.
The Medrash says that the Jews were commanded to cut down their trees and block their water supply [which is normally not done] because Moav is a disgraceful nation. The Radak and Ralbag say that this was only a הוראת שעה - a temporary stopgap measure based on the command of a Navi. So wrote the Rambam in his commentary on the Mishna and that is why the Rambam didn't codify this as a Halacha. But according to the Medrash it wasn't a הוראת שעה but a permanent command, so why did the Rishonim not rule like the Medrash? [See Meshech Chochma Ki Teitzei 23-7 and Kli Chemda Shoftim 20-19].
[עפ"י תורת מו"ר הגאון הגדול רבי ד"י מן זצ"ל]