Synonyms of holy of holies

Noun

1. holy of holies, sacredness

usage: (figurative) something regarded as sacred or inviolable; "every politician fears to touch that holy of holies, the Social Security System"

2. holy of holies, sanctum sanctorum, sanctuary

usage: (Judaism) sanctuary comprised of the innermost chamber of the Tabernacle in the temple of Solomon where the Ark of the Covenant was kept