19b (Beraisa): The Kohen puts each hand on the corresponding foot, and is Mekadesh (pours water on them);

R. Yosi b'Rebbi Yehudah says, he puts one hand on the other, and puts them on his feet, which were one on the other, and is Mekadesh.

Chachamim: One cannot stand this way!

(Rav Yosef): R. Yosi holds that another Kohen supports him.

(Abaye): R. Yosi and Chachamim argue about whether standing Min ha'Tzad (with support) is considered standing.

Question (Rav Sama brei d'Rav Ashi): Why can't the Kohen sit?

Answer (Ravina): Kidush is called "Leshares", and Avodah must be standing.

23b (Beraisa): "La'amod Leshares" teaches that l'Chatchilah, Avodah must be standing. "Ha'Omedim" - the repetition teaches that it is Me'akev.

Megilah 21a (Beraisa): (One may read the Megilah standing or sitting.) This does not apply to Kri'as ha'Torah.

(R. Avahu): We learn from "Stand here with me".

Contradiction: It says "va'Eshev (I sat) on the mountain", and it says, "I stood on the mountain"!

Resolution (R. Chanina): Moshe neither sat nor stood. Rather, he was bent over.

Shevuos 30b: Rav Huna's widow came for judgment in front of Rav Nachman. He could not sit, for a Chacham's wife is like a Chacham.

Question: The judge must sit at the time of the final verdict!

Answer: He sat half-way, like one untying his shoe, at the time.

Rambam (Hilchos Tefilah 5:7): One stands in fear (during Shemoneh Esre).

Hagahos Maimoniyos (7): One may not stand supported. This is a Kal va'Chomer from one who translates the Torah (see 12:11).

Rambam (12:11): The one who translates the Torah (during the Kri'ah) may not lean.

Hagahos Maimoniyos (9): This is from the Yerushalmi. All the more so, the one who reads may not lean.

Rosh (Megilah 3:1): One who reads from the Torah must stand. He may not even support himself, like it says in the Yerushalmi.

Tosfos (19b DH Amidah): Chachamim say that Min ha'Tzad is not called standing. It seems that when one reads from the Torah, he may not stand supported, for in Megilah we say that one must stand. Also the Yerushalmi says that just like Torah was given with fear, we must conduct with it with fear.

Tosfos (19b DH v'Leisev): Rav Sama did not suggest truly sitting, for one may not sit in the Azarah. Rather, he suggested standing supported.

Rivash (266 DH v'Chen): Once, a Beis Din accepted testimony while standing, leaning on a pillar. Perhaps this is considered sitting. If he would fall if it were removed, this is not standing. We hold (Zevachim 19b) like the first Tana of R. Yosi, that standing Min ha'Tzad, i.e. he cannot stand without support, is not called standing. This is like bowing. It is called sitting, for it is not full standing, and is called standing, for it is not full sitting. All the more so standing supported, which is not standing, is called sitting. Also, the law that judges must sit is only an Asmachta mid'Rabanan. If so, l'Chatchilah one may stand supported.

Shulchan Aruch (OC 94:8): One must be careful not to support himself or someone else at the time of Tefilah (Shemoneh Esre).

Magen Avraham (10): The Beis Yosef says that this is not called standing. Hagahos Maimoniyos holds that it is not standing in fear.

Mishnah Berurah (22): According to the first reason, one may lean a little, so that if the support would be removed, he would not fall. According to the second reason, one may not lean at all. In pressed circumstances, one may rely on the first opinion.

Mishnah Berurah (23): One must be careful not to support himself on a Stender. The same applies whenever one must stand, e.g.when he sees a Sefer Torah pass by.

Mishnah Berurah (24): If a sick person knows that he can have intent standing supported, he should do so. If not, he should sit.

Kaf ha'Chayim (32): When praying sitting, one may not lean back or to the side, stretch his legs or cross one over the other, for this is haughtiness. Rather, he sits with his head bent down.

Kaf ha'Chayim (33): Presumably, an obese person may lean.

Shulchan Aruch (141:1): One who reads from the Torah must stand. He may not support himself on the wall or pillar, unless he is obese.

Beis Yosef (DH v'Tzarich): In the Yerushalmi, one was rebuked for reading while supported. One must be careful not to do so, for Chachamim (Zevachim 19b) hold that this is not called standing. Tosfos and the Rosh say that one must be careful about Kri'as ha'Torah. However, the Mordechai brings from the Yerushalmi that permits if he is obese.

Magen Avraham (1): The Bach says that if he read sitting, he was not Yotzei. The Tur and Hagahos Maimoniyos connote like this. However, the Beis Yosef connotes that it is only l'Chatchilah. Also in Sotah (41a) we say that the king reads (Hakhel) sitting. If b'Di'eved he was not Yotzei, we would not permit l'Chatchilah due to the king's honor! We make a similar inference in CM 28 regarding testimony (if it were Pasul b'Di'eved sitting, we would not permit a Chacham to testify sitting). One can distinguish.

Magen Avraham (2 and 426:11): If he leans so much that if the support would be removed he would fall, this is not called standing, so it is forbidden even if he is obese. In CM (17:1), the Rema says that standing supported is called standing. Here, the Tur and Tosfos (Sotah 40b DH veha'Amar) prove from Zevachim that it is not. The Rema saw the Beis Yosef (CM Sof Siman 28) say in the name of the Rivash that if testimony was accepted standing, b'Di'eved it is Kosher. If they stood supported, it is l'Chatchilah, for this is not sitting. The Rema understood that this refers to the witnesses. This is wrong. The Beis Yosef began discussing the judges! Rather, it is a printing mistake. It should say like he wrote in the Shulchan Aruch, that standing supported is like sitting. It refers to the judges. Shevuos 30b connotes like this. Even though there it is also like standing, there we require only Hidur (showing honor). When one must stand, one may not stand supported (Tosfos 19b DH Amidah).Tosfos (19b DH v'Leisev) wrote that even though one may not sit in the Azarah, one may stand supported. This shows that it is not like sitting. We can say that the Isur is only to truly sit, due to honor of the Mikdash. Regarding judges, standing supported is called sitting. Perhaps testimony is more lenient, but there is no necessity to say so. Also regarding Kri'as ha'Torah, one is Yotzei b'Di'eved sitting!

Mishnah Berurah (2): One may not lean even a little, that if the support would be removed he would not fall (unless he is obese).

Mishnah Berurah (4): Also a sick or very old person may lean if it is hard to stand without leaning. He may not lean so much that if the support would be removed he would fall. If he cannot stand without leaning so much, he may. However, he may not lean on the cloth on which we read the Torah, for it is Kodesh. Rather, he leans on the Bimah itself.

Rema: Also the Ba'al Korei who reads must stand with him.

Mishnah Berurah (5): Also the Segan who stands by the Sefer Torah must stand. Sometimes, if the Sefer Torah is long and the Ba'al Korei and the Oleh must read from the top of the column, they need to bow, and they come to lean on the Bimah. This is permitted, for clearly it is not the way of haughtiness. However, after reading the top lines, when he is near the middle of the column and he can read without support, he must erect himself so he will not need to lean at all.

Shulchan Aruch (OC 422:7): The Mitzvah is to read Hallel standing.

Magen Avraham (11): We say Hallel standing, except for Pesach night (at the Seder). One may not support himself on a beam or wall, for standing supported is not standing, like the Tur (141) and Tosfos say.

Bi'ur Halachah (DH Me'umad): Beis Meir argues with the Magen Avraham, and says that for mid'Rabanan laws we are not stringent about standing supported, just like one may stand supported in the Azarah. I agree with him, at least for Hallel. Even if we will say like the Magen Avraham that we do not learn testimony from sitting in the Azarah, we need not be more stringent about Hallel than sitting in the Azarah, for the source to stand for Hallel is from Shibolei ha'Leket 173, who says that it is like testimony. He concludes 'they used to say Hallel standing while slaughtering Korban Pesach, for one may not sit in the Azarah.' He supports his ruling from sitting in the Azarah. Tosfos proves that standing supported suffices for this. All the more so it suffices for Hallel outside the Mikdash! However, there is a hint from the verse "(Hallelu Es Hash-m) ha'Omdim b'Veis Hash-m", so perhaps l'Chatchilah one should be stringent. Surely one may stand slightly supported, that if the support would be removed he would not fall.