Ut quid

Generally, how would you translate ut quid + indicative? For example:

Filii hominum, usquequo gravi corde? Ut quid diligitis vanitatem et quaeritis mendacium? -Psalm 4.3- C. Vulgate

I would go for “why”.

Ditto. See also https://logeion.uchicago.edu/utquid
It is the literal translation of the Greek ἵνα τί

So ut quid is not distinguished from quid?

Quid has a wider semantic range compared with ut quid. While the latter can only mean “why” (cūr, quā dē causā, in classical Latin), the former can also mean what, what kind of, and can be used with other particles. See https://logeion.uchicago.edu/quis

Ok, thank you.

For some reason I was just thinking of that term today and I thought maybe, “to what end”.