The Chassan is learning Maseches Yoma, and of course, the Aseres Yemei Teshuva is about to begin (see note #1), and the speech he prepared, I think, hit the trifecta, and deserves dissemination.
The Mishna in the beginning of Yoma says that the Kohen Gadol must be married when he does the avoda of Yom Kippur. This is based on (Vayikra 16:6) וכפר בעדו ובעד ביתו, he shall achieve forgiveness for himself and his household etc. Chazal darshen that ביתו זו אשתו, the word "household" means his wife. Since the formal vidui mentions his wife, he must have a wife in order to do the Avoda. Why? What is the logic of requiring that the Kohen Gadol be married while he does the Avoda? How does having a wife make any difference in his Avoda?
We find another instance where a public figure needs to have a family. That is the Gemara in Sanhedrin (36b) that is brought by the Rambam in 2 Sanhedrin 3: אין מעמידין בכל סנהדרין לא זקן מופלג בשנים ולא סריס, מפני שיש בהן אכזרייות, ולא מי שאין לו בנים, כדי שיהיה רחמן. One may not appoint to the Sanhedrin one who is very old...nor one who has no children, because they will not have properly developed traits of mercy. But if this is the logic behind the בעד ביתו of the Kohen Gadol, why a wife? Why not a son?
We would like to suggest three possible answers.
The Kohen Gadol must say Vidui for Klal Yisrael. That he can do so is surprising, because vidui is a prime example of something one must do on his own, something one cannot ask someone else to do on his behalf. (See note #2) How can a Kohen Gadol say vidui for Klal Yisrael? The answer is that only once the Kohen Gadol experiences the absolute empathy of ishto ke'gufo can he escape the prison of egotism, and only then can he move from the specific to the general, from the personal to the national, and come to zenith of ערבות that allows him to say vidui for Klal Yisrael as if he were intimately connected with each and every one of them, as if they were all כגופו. Rav Shlomo Zalman Auerbach once went to the doctor with his wife, and told the doctor "עס טוט אונז וויי די פוס," our foot is hurting. The Kohen Gadol can say the same regarding all of Klal Yisrael- but to come to that madreiga requires the first step of having a ריעך כמוך.
(See note #3, and See note #4.)
The Kohen Gadol comes before Hashem and says, Ribono shel Olam, you described Klal Yisrael as יונתי תמתי, Your perfect dove (Shir Hashirim 5:2). I, too, have a perfect dove, my own wife, and she is without any flaw or blemish or imperfection. ועל כל פשעים תכסה אהבה (Mishlei 19:12) You, too, Hashem, look at יונתך תמתך and say כולך יפה רעייתי ומום אין בך.
When a person gets married, his shidduch is a matanah from the Ribono shel Olam, it is the zivug that was fated and intended for him from the moment he was created, and it is the perfect zivug for him. There is nobody else, only יונתי תמתי, and he must thank the Ribono shel Olam for giving him this unique and perfect gift.
(See note #5)
The Gevuras Ari asks why do Chazal assume that Beiso means only his wife, when elsewhere the term might include his sons as well. I would suggest that we find a particular characteristic that is essential to Kehuna Gedola, and that is Tznius. Kimchis, as related in Yoma 47a, had seven sons that were Kohanim Gedolim, and she attributed this amazing accomplishment to her extraordinary Tznius. It is clear that a mother's tznius is a condition precedent for the kedusha of Kehuna Gedola. It is possible (See note #6) that it is also an element in the kedusha itself. If so, it is logical to assume that the word Beiso refers to Kol kevuda bas melech pnima, the tznius of the wife of the Kohen Gadol. Kohanim Gedolim knew that they could only marry a woman that exemplified and embodied the midda of Tznius, and only a Kohen Gadol that has a wife who embodies the midda of tznius can do the avoda.
Along these lines:
The Sforno points out in Parshas Vezos Habracha that the Tribe of Asher was the most successful of the Shvatim and its members were very wealthy, and although most people resent wealth in other people, everyone loved Shevet Asher. This is what is meant by "Retzui Echav." The Sforno does not explain why this was so, he just says that it is an anomaly. But perhaps we can explain it on the basis of the Rashi (Devarim 33:24) that says that Kohanim Gedolim married girls from Shevet Asher- שהיו בנותיו נשואות לכהנים גדולים הנמשחים בשמן זית- and this must be because they were tremendous Tznu'im, as we discussed above. Properly evolved Tznius is not only a matter of modesty in dress, it includes placidity and silence; it certainly means that one avoids flashiness and arrogance and tumul. This kind of tznius, concomitant with good yichus, is a tzniyus of עדינות ואצילות. If Asher was so developed in the midda of Tznius, we can understand why everyone loved them and nobody was jealous of them- because of their tznius.
The Chassan getting ready to propose.