E. Lipiński (1997:461) assumes an eventual connection with PWS *li
‘to, towards’
Possibly related are MSA forms (Blažek 2007:24‒25): Hrs. wəl ‘towards’, Jib. yɔl ‘towards’, Soq. aḷ (more often in di-ˀáḷ) ‘towards’. The etymological background of the MSA forms is, however, rather uncertain, cf. Mhr. hāl ‘to, with, into’ and təwōli ‘to, towards’.
Har. ilā, ilāwa are likely borrowed from Arabic, although -wa in ilāwa is difficult to explain (Arakelova 2001:37, Kogan 2015:181).
The origin of the -āh extension cannot be established with certainty, but as plausibly argued in Huehnergard 2005 (following Brockelmann 1908:334; cf. Pardee 1999:286, 2000:36), it may represent a back-formation from the plural *ˀil-āh-ūma
Loss of -n- in Hbr., Arm. and Sab. (presumably, *ˀinš->*ˀĩš->ˀīš) remains problematic in spite of the obvious presence of -n- in the Hebrew plural form ˀănāšīm (constr. ˀanšē).
PCS
*ˀṯm - to fall into debt, to be guilty
(Kogan 2015: 206)