“The sun stood still”
So the sun stood still and the moon stopped until the nation took vengeance upon its enemies. Is this not written in the Book of Jashar? 'So the sun stopped in the middle of the sky and delayed going down about a full day.' (Joshua 10:13 BSB)
What it sounds like today
A flat report that the sun physically halted in the sky.
The cultural key
The famous 'long day' is expressly a quotation, cited from the Book of Jashar ('Book of the Upright'), a lost anthology of Israel's national poetry also drawn on for David's lament over Saul and Jonathan. Because the source is poetry, its meaning is debated: a literal cosmic miracle, vivid poetic hyperbole for a decisive victory, or an astronomical omen the enemies feared. There is also a polemical edge, since Canaanites worshiped the sun and moon as gods; here Israel's God commands them to halt. The verse is one of several windows onto lost books the biblical writers quoted.
Recovered meaning
The sun standing still comes to us as a line of ancient poetry, quoted from a book now lost, which is why its nature is genuinely debated. Either way its point is that the sun and moon the nations worshiped obey Israel's God.