Before eating bread we wash our hands ritually and recite the blessing
"בָרוּךְ אַתָה ה', אֱ-לֹהֵינוּ מֶלֶךְ הָעוֹלָם, אֲשֶר קִדְשָנוּ בְמִצְוֹתָיו וְצִוָנוּ עַל נְטִילַת יָדַיִם. -Praise are You, LORD our God, King of the Universe, who has sanctified us through His commandments, and has commanded us about washing hands.” If you look at your hand, you’ll see three joints. The first joint is nearest to the tip of your finger. The second joint is at your knuckles. The third joint is closest to your wrist. Today’s daf TB Khullin 106 discusses how much of your hands to have to wash before eating bread.
“The
Sages taught in a baraita: In washing of the hands for
consumption of non-sacred food, one must pour the water on the area that
extends until the joint of the fingers. In washing hands for
consumption of teruma, he must pour on the area extending until
the joint. In sanctifying the hands and feet in the Temple before
the service, he must pour the water until another joint, where
the palm meets the wrist…
“Rav said
this halakha to his students while indicating with his hand the joints
to which the baraita is referring: One washes until here, the
second joint of the fingers, for non-sacred food, and until there,
the third joint, where the fingers join the palm, for teruma. And
Shmuel disagreed and said: One washes until here both for
eating non-sacred food and for teruma, indicating the
more stringent location, the third joint where the fingers join the palm. And
Rav Sheshet said: Until here both for the consumption of non-sacred
food and for teruma, indicating the more lenient location,
the second joint.
“Bar
Hedya said: I was standing before Rabbi Ami, and he said: One washes until
here both for non-sacred food and for teruma, indicating the
more stringent location, the third joint. And do not say that Rabbi
Ami acted this way only because he is a priest and acted stringently
to avoid confusing teruma and non-sacred food. This cannot be, as
Rabbi Meyasha, son of the son of Rabbi Yehoshua ben Levi, is a Levite, and
yet he too said: Until here both for non-sacred food and for teruma,
indicating the more stringent location.” (Sefaria.org translation)
Our
tradition is to be stringent as Shmuel
teaches and wash our hands up to the point where our palms meet our arms.
(Rambam, Mishneh Torah, Sefer Ahavah, Chapter 6, Halakha 4)