In Letter 92 of Senecas's Moral Letters:
Sed tunc quoque cum inter homines est, <non> timet ullas post mortem minas eorum quibus usque ad mortem timeri parum est.
I don't quite understand how the parum est works here. How to translate it literally. First, whether quibus is a dative or ablative. ablative as the means to incite fear or dative as in other parum est examples (see below).
Moreover, the phrase usque ad mortem timeri is also somewhat puzzling. First, usque ad is already implied in the parum est but also it looks like an AcI. (death to be feared), not sure I remember seeing this (I would rather expect ad mortis timeorem with an implicit verb, or ad mortem timendum/timendam)
Doing some corpus search a similar example from the same book is found:
Ad summam sapiens eris, si cluseris aures, quibus ceram parum est obdere
In this case I would not hesitate to read quibus as dative case for a literal: "It is not enough for the ears that vax shuts [them]."
In particular, can we use the dative instead of AcI? for example transform: Parum est latam esse sententiam nisi mandetur executioni to parum sententiae esse lata etc. ?
Edit:
Probably I got usque ad wrong -its meaning is temporal as Leob translation "they were not enough to terrify the soul previous to the moment of death". Simply didn;t understand what was said. So its not AcI and timeri goes with minae and not with mors