Áed's principal church was at Rahugh in modern County Westmeath. He was regarded as a patron saint of the Uí Néill and was said to be a descendant of Fiachu mac Néill. When his brothers refused to allow him a share of the land his father had maintained, Áed carried off a girl who belonged to them. He hoped to force his brothers to give him his patrimony through this injury, but then he met the bishop St Illann, who convinced him to give up his claims to the land and to letthe girl go. Áed mac Bricc's life in the Codex Salmanticensis presents Áed as a peacemaker between Munster and the Uí Néill, and between Mide and Tethbae, befitting his cross-border descent through his mother, Eithne, from the neighbouring Munster people of Múscraige Tíre. An early Latin Life of Áed, perhaps dating from the period 750-850, survives. Although the Life borrows from Adomnán's life of Columba, a copy of which may have been obtained from the nearby monastery of Durrow, its central concerns are with local violence and with the poverty and insecurity of women, especially nuns. Áed seems to have had a profoundinterest in the well-being of religious women. He frequently visited settlements of holy virgins who received him with the respect due to a man of his position. On one occasion, when he perceived that the girl serving him was pregnant he fled from the building both to avoid the pollution and to shame her. She confessed her sins and did penance. Áed was not one to leave someone under his care in a difficult situation; he blessed her womb and the baby disappeared as if it had never been there.
Patronage
Medieval incantations against headache enumerate bodily organs to be protected. One 8th-century Latin hymn from Lake Constance using this device is addressed to St. Aid "mechprech", who has been identified as Aed Mac Bricc, Bishop of Killare, 6th century. An episode in the Life in which he heals Brigit of headache is echoed in the ninth-century Irish life of Brigit. A stone close to the existing church is still associated with the curing of headaches.
