Joshua - Chapter 10

1. What leads King Adoni Tzedek to attack Gibeon and what is the literal translation of "Adoni Tzedek"? Is there any echo of this particular name in the Five Books and in the Abraham story where an alliance of kings also narrated?

“Adoni Tzedek” literally means “Righteous God”; he is identified as the king of Jerusalem. In the story of Abraham and the war of the 5 kings, there was a kind named “Malchizedek” or “Righteous Angel”; he is identified as the king of Salem, which is an ancient name for Jerusalem.
Jerusalem’s status as a holy site – the holiest site on earth – clearly dates back a long way..

2. Is there any reference to a "natural phenomenon" in the victory of Joshua (over and above his own strategy of a night attack) -- and, if so, how does the author of Joshua consider this event and to what source does he ascribe it?

When it was clear that the Jews would defeat the 5-king’s armies in battle, the armies fled, but were struck down by “large stones from heaven”. The text clearly, and rightly, attributes this hail storm as an act of God.

3. Verse 12 and verse 13 deal with another "unusualness in nature" -- this, at the specific request of Joshua. Is it, indeed, correct that not before this day or subsequent thereto "Divinity listened to the request of a human being"?

These verses talk about the sun standing still in the middle of the sky for an entire day; thereby giving the Jews enough time to complete the battle.
There certainly seem to be other instances of God listening to the request of man – I can think of several places where God forgave the Jews at the request, or pleading, of Moses. But this verse is not so much God listening to a request from man - here Joshua seesms to be issuing a battlefield order to his superior officer - and God obeys. That does seem unique.

4. And, the phrase "because Adonai is fighting for Israel," does this appear for the first time in the Tanakh?

Just before the parting of the Sea of Reeds, Moses exclaims “Hashem shall make war for you”. Not exactly the same language, but just about.

5. And, why, at the end of the day, having hung the cadavers, are they removed at sunset?

Is there a mitzvah involved here? Does it have a biblical root or specification?
Perhaps this is based on the Jewish law to burry a dead body with out delay.

Favourite Quote : "There was no day like that before it or after it, that Hashem heeded the voice of man." - Verse 14