From Walsh's History of the Irish Hierarchy With the Monasteries of Each County, Biographical Notices of the Irish Saints, Prelates, and Religious, 1854, c. xliv p. 421
Monastery of Witeschan of which there is but slight mention made. It was situate in the west part of Dublin passing from the cathedral of St. Patrick through the Coombe to the pool of the house of St. Thomas the Martyr. There was an order of friars de penitentia who were also called the sac friars. Their origin was in the year 1245 and their arrival in Ireland took place in 1268. The order did not long survive it was condemned in England in 1307 and its houses passed into other hands and in 1311 the council of Vienne condemned the Order everywhere. This monastery of Witeschan may have been of that Order.