What does Boxing Day have to do with boxing?
c.1400 (attested in Anglo-Latin from mid-13c.), from Old French Judaisme and directly from Late Latin Judaismus (Tertullian), from Greek Ioudaismos, from Ioudaios "Jew" (see Jew). The Anglo-Latin reference is from a special tax levied on the Jews of England. Earlier in same sense was Juhede "Jewish faith, Judaism," literally "Jew-hood" (early 14c.).
The religion of the Israelites of the Bible and of the Jews of today, based on the teachings of the Torah. Judaism involves the belief in one God, whose Chosen People are the Jews. Abraham is considered the founder of Judaism, although Moses, who delivered the laws of God to the Israelites, is also an important figure.