Kedushas HaMakom: The Magen Avraham cited in the Mishnah Berurah (561 s.k. 5) rules that one who enters at the time of the Churban to the makom haMikdash is chayav kares, as nowadays we are all considered tamei mes, and the halachah is like the Rambam (Maaseh Korbanos 19:15) that the kedushah of the Beis HaMikdash is still in place today as we rule kedushah rishonah kidshah l’sha’atah v’kidshah l’asid lavo [the original sanctity given to the Beis HaMikdash was eternal and is still in place today].
Wall of the Azorah: According to a minority of poskim, and most notably the Radvaz (Teshuvah 648, cited in Beis Ridvaz, siman 38) and the Chayei Adam (Sha’arei Tzedek, Mishpetei Eretz, Perek 11, 8) the “Kosel HaMaravi” is the wall of the Azorah.
Based on the above opinion, some are careful to keep at least eleven amos away (the distance of the cheil) from the Kosel HaMaravi, making sure not to get too close to the Azorah. However, the Ridvaz (mentioned above) justifies the minhag ha’oilam to approach the Kosel HaMaravi even if it is the wall of the Azorah. He says that today we don’t stand on the floor of the Azorah, as the Kosel plaza today sits atop many meters of earth that did not exist in the time of the Beis HaMikdash (which will one day be removed), and since גגין ועליות לא נתקדשו – “The rooftops and upper stories were not sanctified”, there is no problem.
Wall of Har HaBayis: The majority of poskim taking on that the “Kosel HaMaravi” is the wall of Har HaBayis. Rav Yechiel Michel Tukachinsky zt”l (Ir Hakodesh V’HaMikdash, vol. 4, pg. 20) writes that it clear and obvious that the “Kosel HaMaravi” is the wall of Har HaBayis. He then goes on to cite twenty clear proofs. R’ Moshe Feinstein zt”l (Igros Moshe, Orach Chaim Vol. 2, siman 113) also takes on like this, and he says that it is permissible to walk close to the “Kosel HaMaravi” like what Yidden have been doing for many generations.
The Orchos Rabbeinu (Vol. 1, pg. 322) writes that once the full length of the Kosel HaMaravi — nearly 500 meters — was uncovered, it became definitively clear that the “Kosel HaMaravi” is the wall of Har HaBayis and not the wall of the Azorah. The Azorah was only a few dozen meters wide, and there is no way that a 500-meter wall could be considered part of it. It has also been accepted throughout the generations like what can be seen in old pictures that they use to daven next to the wall, therefore, it must be that it is the wall of Har HaBayis, as if it was the wall of the Azorah it would be forbidden to go so close, and people would need to keep a distance of 11 amos, and would certainly be careful not to touch it.
Similarly, the Chazon Ish (Orchos Rabbeinu Vol. 2, pg. 186) ruled that one may stand directly against the Kosel since it is the wall of Har HaBayis and not the Azorah. However, one shouldn’t place his fingers inside the wall due to the din of biah b’miktzas shemah biah [that partial entry constitutes full entry].
The Gerrer Rebbe shlita (Siach Sarfei Kodesh, Mechon BaOhalay Tzadikim pg. 49) said that the minhag is to immerse in a mikveh before going to the Kosel HaMaravi due to the concern of entering Har HaBayis whilst being tomei due to keri. Once one immerses in a mikveh he has the status of a tevul yom and is allowed on Har HaBayis (see Mishnah in Keilim 1:8, and Rambam Bias Mikdash 3:5) and may now place his fingers in the wall.
Rav Yisrael Yaakov Fisher zt”l (Even Yisrael, Hilchos Beis HaBechira 2:13; Even Yisrael on Mishnah Berura, siman 561) is mechadesh that one must distance himself 11 thumb breadths (גודלים א''י) from the “Kosel HaMaravi”. He writes that eleven rows of subterranean stones lie beneath the plaza, each row projecting slightly further outward than the one above it, by the width of one thumb. One standing directly against the visible wall is therefore — at the underground level — technically standing within the halachic boundary of Har HaBayis at a location forbidden to a zav and baal keri and even a partial entry constitutes full entry (biah b’miktzas shemah biah).
The Wall Was Never Kadosh: The sefer Mishkenos L’Avir Yaakov (Vol. 2, siman 1) brings in the name of the Maharil Diskin that it is possible that the “Kosel HaMaravi” as we know it, may have been built entirely outside the 500-amah boundary of Har HaBayis and may not be considered kadosh at all. The Mishkenos L’Avir Yaakov then goes on to dispute this, and prove that the Maharil Diskin is wrong.
A Place Where the Shechinah Never Departs: The Maharil Diskin himself said, in spite of this, chas vesholam to argue about the holiness of the Kosel. Chazal teach us about the Kosel HaMaravi: מעולם לא זזה שכינה מהכותל המערבי - ”The Shechinah has never departed from the Western Wall” (Medrash Rabbah Shemos 2:2; Zohar HaKadosh Shemos Daf 5). We also learn: נשבע הקב''ה עליו שלא יחרב לעולם – “Hashem swore it would never be destroyed” (Medrash Rabbah Shir HaShirim 2:22; Bamidbar 11:3). The Maharil Diskin’s opinion was only relevant when it comes to questions such as inserting fingers into the wall. Regarding that we can argue that it may not have the kedusha of Har HaBayis, however, regarding the hashro’as HaShechinah [spiritual reality of the Shechinah], that is always certainly there.
