Franz Rosenthal has a philological monograph on the historical meaning and usages of the term 'ilm in Islam. It's called Knowledge Triumphant (1970). Now I don't understand if this is the the correct sequence of adjective and noun in English. If Triumphant is an adjective, should't it be reverse: Triumphant Knowledge?
The postpositive position for adjectives is rare in English (though there are lists of well-known exceptions. One such list appears in the Why inspector-general and not general inspector ... thread.)
It can be seen that quite a few of these terms are held onto by the legal profession, in heraldry, and in names of distinguished ranks and posts, organisations, and dishes – presumably for the cachet effect.
Here, an unusual pairing is used for dramatic effect / emphasis / the cachet value mentioned. It would sound unacceptable under most other circumstances. These things tend to be widely accepted or widely considered bombastic. Perhaps contrasting examples are 'Amnesty International' and the 'Church Universal and Triumphant'. It's a matter of how they come to be accepted or not, rather than whether or not they are grammatical.
As EA noted, post position adjectives are rare in English, which prefers that you know the color of the red house first. It's frozen in a few instances like "attorney general", where the high rank comes before the title, unlike "patent attorney" or "ambulance-chasing attorney", where the modifiers comes first.
Switching positions emphasizes the noun, giving a dramatic tone, but at the risk of sounding arch if not archaic. As a cautionary tale consider the case of Channing Pollock, who was a composer and playwright of the 19-teens and 1920s. He had some middling success, contributing to various Ziegfield Follies. In 1931, his play The House Beautiful was demolished in a review by Dorothy Parker who mocked the pretentious, reversed title with
The House Beautiful is the play lousy.