Spitting is important to the Jews, they're commanded
to spit upon smelling food and many of them spit on the
floor of the synagogue, during a prayer which makes a
thinly veiled reference to Jesus.
The Shulchan Aruch, known in English as the Code of Jewish Law, is a written manual of halacha (Jewish law), authored and published by Rabbi Yosef Karo in the 16th century. It's the most widely accepted and authoritative compilation of halacha since the Mishneh Torah or even the Talmud itself.
"Chapter 33. Things that are forbidden because they are dangerous Y
No. 4: A person should always remember that, to
smell food, you should spit ascended saliva,
rather than swallow it, because if he had
swallowed, may expose themselves to danger, Gd
forbid."
"Spitting on the Beit Knaset (synagogue)
floor during Aleinu (prayer) is a common
Chabad (Hasidic Jewish sect) practice; they
do not find it offensive or disgusting in
any way." Y
"The Aleinu
prayer concludes every service.
And after we say the first line of this
prayer, we spit. In this first line we
praise the Master of all things that He
has not made us like the nations
of the world, nor caused us to be like the
families of the earth; that He has not
assigned us a portion like theirs, nor a lot
like that of all their multitudes, for they
bow to vanity and nothingness - [SPIT]. But
we bend the knee, bow down, and offer praise
before the supreme King of kings..." Y
