Yoma 69— the Anshei Knesses Hagedolah were given the honorific “Hagedolah” because ‘hecheziru atara liyoshna’, they brought the crown back to its glory. As the destruction of the first Beis Hamikdash drew closer, and the Jews were subjected to increasingly harsh and painful experiences, the Navi Yirmiahu removed the word ‘nora,’ awesome, from the description of Hashem in our prayers. He said, "Strangers are crowing in His sanctuary. Where are His awe inspiring acts?" Later, when the Jews were exiled, Daniel took off ‘gibor’. He said, "Where are Hashem’s great powers? How can we describe Him with terms that are contradicted by our daily experience?" But the Anshei Knesses Hagdolah came later and said "On the contrary! His gevura is his arichus appaiyim, his patience, to the resha’im, and his morah is what maintains our existence despite the mortal hatred of the nations among whom we are interspersed."
The idea here is that we cannot describe the actual ‘character’ of Hashem, but instead only describe the 'characteristics' that we observe through His actions in our world. This is what is stated in ‘An'im Zemiros’ (from Reb Yehuda Hachasid or an approximate contemporary), that ‘Himshilucha velo kefi yeshcha, vayashvucha lefi ma’asecha.’ /"They likened You, but not as You really are. They tried to describe you according to Your deeds." What we say about Hashem is, first of all, only a mashal, and second of all, only what we perceive through His behavior. The Rambam says “Kol hate’arim she’anu omrim al Hashem Yisbarach ein hakavana al te’arim atzmi’im chas veshalom rak al te’arei hape’ulos.” If we do not see a certain trait in Hashem’s relationship with this world, we cannot honestly describe Him with terms that are inconsistent with what we perceive.
An example of this: the Gemara (Shabbos 88a) says,
Rabbeinu Tam asks there, that in that passuk in Shir Hashirim, it is not Klal Yisrael being compared to a Tapuach, but rather Hashem! So why does the Gemara say “Why is Klal Yisroel like the Tapu’ach?” It is not us being described, it is Hashem! The Anaf Yosef in the Ein Yakov brings down the Nefesh Hachaim that answers that if Klal Yisrael perceived and compared Hashem to ‘tapuach’, this is definitely because Klal Yisrael is comparable and their behavior is similar to ‘tapuach’, because “kederech she’anachnu misra’im lefanav yisbarach, kach hu yisbarach shemo ba lei’ra’os el ha’olamos al zeh ha’hadraga vehashiur mamash.” From this vort you see a two very important concepts: Hashem appears to us in a fashion that reflects our behavior; and that what we call His Semblance is just one of the ways that He communicates with us through His behavior. Since this is His manner of communication, it follows the rule of Middah keneged Middah.
To see R Chaim Volozhener inside, see his pirush on Shir Hashirim there, and also in a hagaha in Nefesh Hachaim 1:9, and see there 1:7. See also a very similar approach in the Alshich on Shemos 34:6, where he discusses the Bris of the thirteen Middos.
Also, see the Netziv in Shemos 3:14, where Hashem told Moshe “Ehyeh asher Ehyeh.” The Netziv explains that Hashem meant that the Geula will take place, but the manner of its occurrence is not clear yet, because it depends on the ko’ach of the m’kablim: “Ehyeh misnaheig b’p’ulasi k’fi asher ehyeh b’ko’ach Yisrael asher yitnu li.”
Now, these are supposed to be "Divrei Torah that require some thought." If you have been paying attention, you will have noticed that the Gemara about the Anshei Knesses Hagdola and the words of Rav Chaim Volozhiner seem to be totally and absolutely incompatible. How can we say that it is impossible to describe the essence of the Ribono shel Olam, and that our descriptions only interpret the characteristics we observe, when those characteristics are a reflection of our behavior? If what we observe reflects our own behavior, how can we describe Hashem on the basis of what we observe? If Hashem speaks to us through our own reflection in a mirror, then what we are observing is, in the final analysis, us, not Hashem. What we are describing is ourselves!
I imagine that the answer is that we do not create our God, or change His traits, or even His essential relationship with our world, with our behavior. It is only the superficial manner of their expression in the physical world, and our ability to perceive the Middos, that changes according to our behavior. The point of the Gemora about the Anshei Knesses Hagedola is that although Hashem's middos appear to change as they reflect our behavior, if one is truly conscious and aware, he will be able to perceive the essential characteristics of Hashem despite the fog and confusion of the ostensible. The Nefesh Hachaim serves to explain why Yirmia'hu and Daniel held that we are constrained to limit our description of Hashem to how we understand His interaction with the world; if hester panim means that we misunderstand what is going on, we must accept the ostensible as the only way we are entitled to describe Him. It was only through the Anshei Knesses Hagedolah's teachings that we, as a nation, were taught to understand the truth behind the reality. Only once we understood that truth could we go back to describing Hashem in the terms used in this parshah.
(We mentioned the Anshei Knesses Hagedola. Speaking of the Knesses Hagdola, the passuk here in 8:10 mentions the din of birkas hamazon, ve'achalta vesavata. The Knesses Hagdola’s shittah, (UPDATE: This Knesses Hagedola has nothing to do with the Anshei Knesses Hagedola. This one is a seventeenth century author, Harav Chaim Benbenishti, who is one of the great poskim of Klal Yisrael. I only put this here because Birkas Hamazon is in the parsha as well, and the tzushtell made me smile.) which is also the shitta of the Pri Megadim brought in the Mishna Berura 210, is that an achila of a kezayis in more than an achilas prass is mitztaref and is mechayev bentching midoraiso– but only if he is savai’a. (Chaim B pointed out that the Minchas Chinuch, and most poskim, hold you need both kezayis toch kedei achilas pras plus Sevi'a.. I point out that the Chasam Sofer in the Tshuvos OC 49 says "karov le'vadai" that in the time that bracha was in the food, and a person would be savei'a with less than a kezayis, then he would be chayav to bentch mid'oraysa. Also, Reb Moseh in OC 1:76 says absolutely not; you definitely need a kezayis.) On the other hand, it seems to me that if one would do so on Yom Kippur, he would not be chayav koreis. (Again, Chaim B. said that since Yom Kippur is not a din of Achila, it's a din of Inui, it has nothing to do with achilas pras, and that's why the shiur is kekosves hagas. I disagree with him; not all inuyim are assur midoraysa. Chazal understood that inuy deorasyas means not eating or drinking, and eating means kezayis toch kdei achilas pras. If Chaim B were right, our hanhaga of feeding cholim on Yom Kippur not kedei achilas pras would be futile and meaningless. Even Reb Chaim Brisker (Griz 2 Shvisas Asor 8) that holds that a choleh has not reason to avoid TKAP and may eat without any constraints on Yom Kippur, he agrees that the din of TKAP does apply to someone who is not deathly ill but must eat to prevent becoming ill.) So, (assuming I'm right and Chaim B is wrong,) strangely enough, if one would eat a kezayis of bread on Yom Kippur but not toch kedei achilas peras, and he was savei’a, he would be pottur as far as Yom Kippur, but he would have to bentch mid’oraysa. UPDATE: I've been thinking about this, and I decided it's too strange to be true. I've decided that the Knesses Hagdola would hold that svi'a without TKAP would be chayav on Yom Kippur just like it's chayav in Birkas Hamazon de'oraysa.)