Shevuos Daf 16 חג השבועות דַף 16

Regarding the requirements for being mekadesh the Mikdash and Yerushalayim, Rav Huna says: בכל אלו תנן – we learned in our Mishnah that sanctification is effective only with all of these requirements listed. Rav Nachman says: באחת מכל אלו תנן – we learned in our Mishnah that sanctification is effective even with only one of these requirements. This machlokes hinges on how to explain the fact that Ezra was mekadesh Yerushalayim and the second Beis Hamikdash without a king and no אורים ותומים. Rav Huna holds: קדושה ראשונה קידשה לשעתה וקידשה לעתיד לבא – the original kedushah [of Yerushalayim and the Beis Hamikdash] sanctified [its site] for its time and forever and needed no sanctification in Ezra’s time. Rather, Ezra’s was performing a זכר בעלמא – mere remembrance of the initial sanctification, and no inference can be drawn from its lacking a king and אורים ותומים. Rav Nachman holds לא קידשה לעתיד לבא, so Ezra needed to be mekadesh it again. Since he did so without a king and אורים ותומים, this proves that not all elements are necessary. The Gemara proves that the question of קדושה ראשונה is a machlokes Tannaim.

The Mishnah on Daf 14b taught that if one became tamei in the Mikdash and forgot either his tumah or that he was in the Mikdash, and he either bowed or delayed leaving in some way, he is liable to a korban. The Gemara asks for the source that one is liable for tumah contracted while in the Mikdash (since the passuk prohibits “being metamei” the Mikdash, and this person was metamei it as soon as he became tamei). It answers that there are two pesukim: "את משכן ה' טמא" – he has contaminated Hashem’s משכן, and "כי את מקדש ה' טמא" – for he has contaminated Hashem’s Mikdash. אם אינו ענין לטומאה שבחוץ – if [the second passuk] has no application for tumah contracted outside the Mikdash (since it is already known), תנהו ענין לטומאה שבפנים – apply it instead to tumah contracted inside the Mikdash, teaching liability for not leaving immediately. Although both pesukim are necessary to teach liability for entering either the משכן or the Beis Hamikdash while tamei (because neither can be derived from the other), the Gemara explains that the word משכן or מקדש could have been used in both pesukim, and the changed terminology indicates a second derashah.

The Mishnah on Daf 14b taught that if one became tamei in the Mikdash, and then bowed, or delayed long enough to bow, or exited via a long route, he is liable. Rava explained that bowing without delaying is only liable שהשתחוה כלפי פנים – where he bowed towards the inside of the Mikdash (towards the היכל), which is considered bowing. אבל השתחוה כלפי חוץ – But if he bowed towards the outside, שהה אין – then if he delayed he is liable, but not if he did not delay, since this is not considered bowing. [The Gemara records another version of Rava’s statement.] Bowing which does not entail “delaying” is כריעה בעלמא – merely kneeling and bowing which does entail delaying (which is the delay period described by the Mishnah) is פישוט ידים ורגלים – outstretching arms and legs (prostration). Amoraim dispute the exact length of this time period. [In addition to these two types of bowing, a Baraisa defines "קידה" as על אפים – bowing down upon one’s face.]