Ministry of Abnegation
The Ministry of Abnegation was a ministry of the Covenant, formed alongside the empire in around 852 BCE. They had oversight of the Ascetics, after one of the terms of the Writ of Union dictated that the Sangheili's original Ascetic guard was to be dissolved and reconstituted into the San'Shyuum-controlled ministry. Alo Sebukah served as the final vice minister of the Ministry of Abnegation. Following the demise of the Covenant and its ministries during the Great Schism, the Ascetics were revived as an independent order by Sangheili warriors.
Abnegation to deny or renounce something, which fits with the Asceticism's role of self-denial.