Despite his political eminence and clerical office, he was a man of ruthless character and violent temper, who once tried to murder a judge, and was later directly responsible for the death of his intended replacement as Prior.
At Pentecost 1462 Sir Robert Dowdall, the Chief Justice of the Irish Common Pleas, went on a pilgrimage to the "holy well" at Clonliffe, in north Dublin.
[9] He probably owed his immunity from punishment to the influence of the powerful Anglo-Irish magnate Thomas FitzGerald, 7th Earl of Kildare, later Lord Chancellor of Ireland, who acted as Keating's patron.
He was later accused of bankrupting it: in his defence, he pointed out that in 1467 his superiors in Rhodes had increased the annual payment due to the Order's central fund from the Kilmainham house from £40 to £70 without consulting him.
However, he was in temporary disgrace in 1467, when King Edward IV sent the notoriously ruthless John Tiptoft, 1st Earl of Worcester (nicknamed "The Butcher of England") to be Lord Lieutenant of Ireland.
[11] Worcester held a Parliament at Drogheda where he proceeded to deal mercilessly with his enemies, including the Earl of Kildare, who fled abroad, and Keating, who was briefly imprisoned and subjected to a heavy fine.
The Lancastrians during their brief restoration had also indirectly strengthened his political position by executing his enemy, Worcester, who was a committed Yorkist and perhaps the most hated man in England.
Though not a founder member, Keating was later elected one of the knights of the Brotherhood of Saint George, the short-lived military order set up in 1470 for the defence of the Pale.
The Anglo-Irish nobles, led by the immensely powerful Gerald FitzGerald, 8th Earl of Kildare and his father-in-law Baron Portlester, simply refused to recognize his authority:[16] Keating, who had assumed the role of Constable of Dublin Castle, apparently without any legal right to it (Richard Archbold was later described as the "rightful Constable" and had letters patent to prove his appointment)[17] played a key role in these events by refusing Lord Grey entry to the Castle.
He was allowed to retain the office of Constable of Dublin Castle,[18] despite the rival claim of Richard Archbold, on condition that he repair the drawbridge, which he had destroyed to impede Grey's entry.
Both the Papal Legate, Octavian De Spinellis, and the Archbishop of Dublin, John Walton, expressed their outrage at Keating's conduct and demanded Lumley's release.
The downfall of the House of York at the Battle of Bosworth in 1485, and the establishment of the Tudor dynasty under King Henry VII came as unwelcome news to the largely pro-Yorkist Anglo-Irish nobility.
[19] Simnel, whose true origins are something of a mystery, was an imposter, but is known to have borne a striking resemblance to the real Warwick, who was a prisoner in the Tower of London, where he remained until his execution in 1499.