OET interlinear PSA 89:4

uW Translation Notes:

Note 1 topic: grammar-connect-time-simultaneous

עַד־ע֭וֹלָם אָכִ֣ין זַרְעֶ֑⁠ךָ וּ⁠בָנִ֨יתִי לְ⁠דֹר־וָ⁠ד֖וֹר כִּסְאֲ⁠ךָ֣ סֶֽלָה

(Some words not found in UHB: made covenant to,my_chosen_of,one sworn to,David servant_of,my )

If it would be more natural in your language, you could express this as an indirect quotation. Alternate translation: [I swore that I will establish his seed until forever, and I will build up his throne to generation and generation]

Note 2 topic: figures-of-speech / metaphor

אָכִ֣ין זַרְעֶ֑⁠ךָ

(Some words not found in UHB: made covenant to,my_chosen_of,one sworn to,David servant_of,my )

Here Ethan is speaking as if descendants were seed that is planted. Your language may have a comparable expression that you can use in your translation, or you could state the meaning plainly. Alternate translation: [I will establish your descendants] or [I will establish your offspring]

Note 3 topic: figures-of-speech / metaphor

וּ⁠בָנִ֨יתִי לְ⁠דֹר־וָ⁠ד֖וֹר כִּסְאֲ⁠ךָ֣

(Some words not found in UHB: made covenant to,my_chosen_of,one sworn to,David servant_of,my )

Ethan is using build up your throne as a common expression of the culture to mean “firmly establish your rule.” If this phrase does not have that meaning for your readers, you could use a comparable expression from your language that does have that meaning, or you could state the meaning plainly. Alternate translation: [I will firmly establish your rule] or [I will make your kingdom strong]

Note 4 topic: figures-of-speech / metonymy

כִּסְאֲ⁠ךָ֣

(Some words not found in UHB: made covenant to,my_chosen_of,one sworn to,David servant_of,my )

Here, your throne represents royal authority and rule. If it would be helpful in your language, you could use an equivalent expression or plain language. Alternate translation: [your royal authority]