The Real Fight

The Sefer Hachinuch says about the mitzvah not to eat the gid haneshe: משרשי מצוה זו, כדי שתהיה רמז לישראל, שאף על פי שיסבלו צרות רבות בגלות מיד העמים ומיד בני עשו, יהיו בטוחים שלא יאבדו, אלא לעולם יעמד זרעם ושמם, ויבא להם גואל ויגאלם מיד צר. ובזכרם תמיד ענין זה על יד המצוה שתהיה לזכרון, יעמדו באמנתם ובצדקתם לעולם. ורמז זה הוא לפי שאותו מלאך שנלחם עם יעקב אבינו, שבא בקבלה (בר''ר עח) שהיה שרו של עשו, רצה לעקרו ליעקב מן העולם הוא וזרעו ולא יכול לו, (שם לב כו) וצערו בנגיעת הירך. וכן זרע עשו מצער לזרע יעקב, ולבסוף תהיה להם תשועה מהם. וכמו שמצינו (שם שם לב) באב שזרחה לו השמש לרפאתו ונושע מן הצער, כן יזרח לו השמש של משיח וירפאנו מצערנו ויגאלנו במהרה בימינו, אמן.  According to the Chinuch the point of the mitzvah is to strengthen our faith in Hashem by remembering that Yaakov was victorious over the angel of Esav that came to kill him.  Rav Bakshi-Doron asks if this is what we are supposed to be remembering, why would we choose an event from the fight with the angel of Esav and not the fight with Esav himself?  The fight with the angel is shrouded in mystery and from the text we don't even see the man that Yaakov fought with has anything to do with Esav?  Furthermore, Yaakov gets wounded in this fight but in his "fight" with Esav he comes out completely unscathed, seemingly that is more fitting to strengthen our faith?  And why is the whole fight with the angel of Esav unclear from the Chumash and even from the commentary of our sages its still unclear what was going on?

He explains that the Torah is teaching us what is the true fight against Esav.  If Esav is coming with an army its easy to recognize the danger that awaits.  There isn't much room to debate that maybe he has just come to offer his assistance and means no harm.  However, when the angel of Esav comes it is much harder to see the danger ahead.  When he comes with promises of education, enlightenment, arts, sophistication, technology and money it is very difficult to see the danger in it.  Esav says this well help you.  We will bring you out of poverty and the entire world will be opened before you.  We have hidden our knives in the kitchen and will invite you into our house.  This danger is indeed shrouded in mystery.  Has Esav actually had a change of heart, has he let the past be past and decided to actually act as עשו אחינו or is it a ploy to attempt to take the Jew out of the Jew?  This is why remember the fight with the angel of Esav for this danger requires more of a reminder.  The reminder is where Yaakov was hit in order to show the main test is when the going gets tough we must not forsake our faith and must keep in mind that tomorrow the sun will shine again and we shall be healed in its rays.
The following excerpt is from עובדות והנהגות לבית בריסק עמ' יז.