εἰς τόπον χλόης, ἐκεῖ με κατεσκήνωσεν, > ἐπὶ ὕδατος > ἀναπαύσεως ἐξέθρεψέ με- 22.2
Here I’d like to know what sense you would say that ἐπὶ ὕδατος is used. Locative? Instrumental?
Impossible to say precisely of course, but basically locative, of the environment in which he was raised. Not instrumental: “he brought me up me on water”—i.e. with water—would be plain dative.
It makes more sense in the context of the sheep being cared for by a shepherd. The shepherd has pastured and raised me in a grassy place by calm waters. This mental context explains why the LXX translator thought to use ἐξέθρεψε for a Hebrew word meaning “leads”.
Uses ἐκτρέφω to mean παρέχω ‘of natural objects, yield, produce’ and so παρέσχετο με “provided to me” and the verse should begin with νομός ‘pasture’ (not τόπος).
That is all nonsense. It’s not τόπον, it’s εἰς τόπον, and followed by the ἐκεῖ.