A man must not carry a sword, bow, shield, lance, or spike on the Sabbath... Rabbi Eliezer said, "But they are adornments [which are worn rather than carried]."
The sages said: "They are merely shameful, for it is said:
'And they shall beat their swords into plowshares
And their spears into pruning hooks;
Nation shall not take up
Sword against nation;
They shall never again know war'" (Isaiah 2:4).
- Mishnah, Tractate Shabbat