Gemara

(R. Avahu): Disgracing Netilas Yadayim causes poverty.

(Rava): This is only if he did not wash at all. If he washed minimally, it is fine.

Rejection: This is wrong!

(Rav Chisda): I pour generous handfuls over my hands, and Hash-m fills my handfuls with goodness.

Chulin 106a (Beraisa): For Chulin, one must wash until the Perek (joint);

For Terumah, one must wash until the Perek;

Washing the hands in the Mikdash (before Avodah) must be until the Perek.

Rav showed his Talmidim how far to wash for Chulin, and how far for Terumah.

Shmuel was stringent. He required the same amount for Chulin as for Terumah.

Rav Sheshes was lenient. He required the same amount for Terumah as for Chulin.

R. Ami was stringent. He required the same amount for Chulin as for Terumah;

Do not say that he was stringent only because he was a Kohen. R. Meisha was just as stringent, and he was a Levi (the grandson of R. Yehoshua ben Levi)!

Rishonim

Rif (Berachos 41a): A Beraisa obligates washing until the Perek for Kidush, Terumah and Chulin. We conclude like R. Yehoshua ben Levi, who requires until the Perek for Chulin and Terumah.

R. Yonah (DH li'Trumah): Shmuel is lenient for Terumah like for Chulin. R. Yehoshua ben Levi is stringent for Chulin like for Terumah. Rashi says that Rav holds that two joints of the fingers suffice for Chulin, but Terumah requires until the ends of the fingers, i.e. all three joints. Shmuel holds that two joints of the fingers suffice for Chulin and Terumah. R. Yehoshua ben Levi requires all three joints even for Chulin. The Halachah follows him. Why didn't we challenge Shmuel and R. Yehoshua ben Levi from the Beraisa, which gives different Shi'urim for Chulin and Terumah? Chachamim of France answer that the Amora'im did not know the Beraisa. If so, it suffices until the ends of the fingers, for R. Yehoshua ben Levi says so and he is the most stringent opinion.

Rambam (Hilchos Berachos 6:4): One must wash the hands until the Perek.

Rosh (Chulin 8:11): We concluded that we are stringent to wash until the Perek for Chulin and Terumah, like R. Yehoshua ben Levi. The Rif's text says that Kidush of hands and feet is until the Perek, and for Chulin, until the Pekak, i.e. the joints at the end of the fingers. The Perek is where the hand meets the arm. Rav's text said that for Chulin we wash until the Pekak, and for Terumah until the Perek. Shmuel's text said that for both of them we wash until the Perek. Also Hilchos Eretz Yisrael and Sefer ha'Zahir say that we wash the entire hand for Chulin. The Rif did not say 'to be stringent.' Since he requires until the Perek, it is clear that this is a stringency. This is an excessive stringency. This is not the custom. According to R. Yehoshua ben Levi, since all of them have the same Shi'ur, why weren't they taught together? It is difficult to say that the Tana heard the laws one at a time, and taught each after he learned it.

Tosfos (106b DH Amar): Rashi explains that Shmuel does not argue with the Beraisa. He was a Kohen, therefore he was stringent for Chulin like for Terumah. However, why was Rav Sheshes lenient even for Terumah? We must say that he explains that the Beraisa obligates until the first joint of the fingers for Chulin, and until the second joint for Terumah. He is lenient, i.e. more lenient than Rav and Shmuel. R. Avraham says that the joint for Chulin is until the ends of the fingers, and for Terumah the entire palm, i.e. until the wrist, and for Kidush, until the elbow. He supports himself from Sefer ha'Zahir. He erred. Erchin 19b proves that Kidush is not until the Atzil, i.e. the elbow. However, he explains that Atzil is the shoulder. Zevachim 18b and Ohalos 1:8 refute this.

Poskim

Shulchan Aruch (OC 161:4): One must wash the hands until the wrist.

Taz (5): Immediately after the hand finishes is the Kaneh Shel Zero'a. One must wash until the beginning of the Kaneh, i.e. until the end of the hand, according to the Rif.

Kaf ha'Chayim (35): The Kesef Mishneh and others say that the Rambam holds like the Rif. The Rosh (Teshuvah 48:4) says that the Rif's opinion is primary. Also the Ari Zal says so, and likewise in the morning one should wash until the wrist.

Shulchan Aruch (ibid.): Some say that one must wash until where the fingers connect to the palm. It is proper to follow the first opinion.

Beis Yosef (DH Shi'ur): The Roke'ach follows the Rosh's text, and says that until the second joint suffices for Chulin. The Rosh and R. Yonah say that the Rif's text of the Beraisa requires until the wrist for Kidush and Terumah, and until the ends of the fingers for Chulin. We rule like R. Yehoshua ben Levi, who requires until the wrist even for Chulin. The Rambam wrote Stam. It is not clear what he holds. The Rashba wrote like the Rif. R. Yerucham says that this is the custom. This is proper. Since it is not an exertion, we should [fulfill all opinions, and] avoid the argument. This is no worse than Rav Chisda, who said 'I pour generous handfuls over my hands, and Hash-m fills my handfuls with goodness.' It is good to stipulate that he does not accept this for an obligation, rather, as an optional matter. If once he is unable to do so, he will not need to be stringent like his custom. It is proper to stipulate about every stringency that one accepts.

Taz (6): Regarding this stringency, there is concern for onlookers, who will think that this is letter of the law, and sometimes they will see the person wash only like letter of the law, and say that he did not wash properly. It will seem to them as if there are two Toros, Chas v'Shalom! Also, they will denounce them. In Gitin 5b, we say that one should not be stringent about a Get for this reason. The Rosh (Pesachim 1:10) says that it would be better to bless Leva'er Chametz, but we bless Al Bi'ur Chametz, so people will know that also this is fine. I say that the Shulchan Aruch said to be stringent only in private, but not in front of others. I say that one who is lenient in all places does not lose, since the Halachah follows the lenient opinion in Netilas Yadayim (160:11). Rav Chisda's adage does not apply to. He refers to pouring much water in the place that must be washed, but not where there is no Mitzvah to wash.

Magen Avraham (12): Also the Zohar says like this opinion.

Magen Avraham (13): If the [entire] hand is dirty, all agree that one must wash [all of] it.

Gra: The latter opinion is like Rashi and Tosfos, who say that the conclusion is like Shmuel. However, R. Avraham says that 'until the Perek' for Chulin is until the ends of the fingers. If so, Shmuel requires until the wrist, like the first opinion. Tosfos rejected this. The Rif holds that Shmuel's text of the Beraisa says 'Perek' regarding all of them. Rav text says 'Pekak' regarding Chulin, and Rav Sheshes' text says Pekak also regarding Terumah. We hold like Shmuel. This is the first opinion in the Shulchan Aruch. The Ramban explains that Terumah is until the second joint, and Chulin is until the ends of the fingers. The Yerushalmi says so. Also the Bavli connotes like this. It says they permitted eating with a cloth [over one's hands, without washing, for Terumah, but not Tahor Chulin. This shows that Chulin is more stringent than Terumah.] The Ro'oh and Ritva agree. However, letter of the law they hold like Rashi and Tosfos and our text of the Gemara, like R. Chananel says. The Rif supports them. He wrote Kidush, and then Chulin, and then Terumah. [This connotes that Terumah is most lenient.] The Ro'oh says so. We can say that [also] the Rif holds like the latter opinion! The Rashba said that there is no proof from a cloth. We are more lenient for Kohanim, since they are zealous. We can explain the Yerushalmi and Bavli to say that Terumah is until the wrist, and Chulin until the ends of the fingers. [Rav] is stringent an extra Perek, to make Chulin like Terumah, and Terumah like Kidush. Shmuel is stringent about both of them like for Kidush. According to Rashi, there is no stringency of Terumah. Rav Sheshes require until the ends of the fingers for both. He is more lenient than Rav and Shmuel, but even he is more stringent than the Beraisa. We need not say like Tosfos, that Rav Sheshes holds that the Beraisa requires only until the first joint. We hold like Shmuel. This is the first opinion.

Damesek Eliezer: According to the Ran's text of the Rif (Chulin is until the Pekak), we cannot say like the Gra that the Rif holds like the latter opinion in the Shulchan Aruch.

Mishnah Berurah (21): We do not protest against one who wants to be lenient like the latter opinion, but l'Chatchilah one should be stringent like the first opinion. This is the custom.

Mishnah Berurah (22): In pressed circumstances, if one has limited water, he may rely on the latter opinion.

Bi'ur Halachah (DH v'Ra'uy): The Beis Yosef says that the latter opinion is primary, just it is proper to be stringent since it is not hard. This is not clear. Ma'amar Mordechai writes that the simple reading of the Rambam is like the Rif, since he wrote Stam 'until the Perek'. He must have had the Rif's text. 'Until the Perek' is a specific place, i.e. the wrist. According to Tosfos, he should have specified which joint! R. Chananel and the Rashba hold like the Rif. The Rashba's Perush does not have the difficulty with Tosfos' Perush that the Gra aroused. Semag holds like the Rashba, and says that also the Aruch does. Or Zaru'a says that one should be stringent. Surely letter of the law one should be stringent like all of these opinions, especially since the Yerushalmi supports it. The Magen Avraham brings from the Zohar that it is until the ends of the fingers. This is not such a proof. Also the Gemara brings different opinions! Atzei Almogim says like I said. He says that washing only until the ends of the fingers is 'disgracing Netilas Yadayim.' I say that in pressed circumstances, one may rely on the lenient opinion. Since the custom is like the first opinion, one should not wash with only a Revi'is, for it is very likely that he will not wash the entire hand. One must be very careful about this!

Kaf ha'Chayim (37): Eliyahu Rabah and Mishbetzos Zahav rejected the Taz. When there is an argument, we follow the Mekubalim. Especially here there is concern for a Safek Berachah (the first opinion forbids blessing if he does not wash until the wrist). There is no need to explain the Zohar like the Magen Avraham. Surely the Ari Zal and R. Chaim Vital saw the Zohar, and they say to wash until the wrist! If one does not have enough water to wash until the wrist, he does not bless with Shem and Malchus.

Ma'ase Ish (6 p.102): Once, a man was invited to a Seudas Bris. The Chazon Ish said that he need not go, for presumably some of the people there (even if they are all Bnei Torah!) are improper, for they do not wash properly.