On 12 December 443, Nomus was ordered to strengthen the defence of the Danube limes, recently affected by the attacks of the Huns of Attila: the forts were rebuilt and the frontier garrisons restored to their nominal strength.
However, when Attila resumed his raids in 447, he did so through the provinces of Scythia Minor and Moesia Inferior, skirting around the fortifications built by Nomus to the east.
Nomus (chosen as loyal supporter of the powerful eunuch Chrysaphius) and his companion went to meet Attila, who treated them badly at the beginning, but later succumbed to their oratorical arts and to the gifts they had brought: Attila would accept the terms of peace of 448, he would stop attacking the Emperor Theodosius II, and give up the strip of land south of the Danube obtained with the peace of 448; it seems that the granting of the release of many Roman prisoners was a concession made personally to the two prestigious guests.
In 449, the monk Eutyches asked Emperor Theodosius to summon the Council of Chalcedon: Chrysaphius and Nomus joined him and obtained the proclamation.
During his tenure as magister officiorum, he was contacted by two nephews of the bishop Cyril of Alexandria; he helped them by lending some money, but he required very high rates of interest.