Ultimately from Proto-Semitic *ʕall-, *ʕaly- (“to be high; exalted”), from Proto-Afroasiatic *ʕal-, *ʕVl(ay)- (“to be high, tall; to rise, ascend”).
Cognate with Hebrew עָלָה (ʿalá, “to ascend, rise, grow, develop”), Hebrew עלי (ʿeli, “ascent”) and thereby Eli.