The following is an extract from Lisburn Rural District, Co. Antrim Official Guide c.1967
Ballinderry.
… Between Ballinderry and Lough Neagh is Portmore Lake (otherwise known as Lough beg) and on the shores of this is an old ruined church. The structure has associations with Jeremy taylor, Bishop of Down and Connor and author of Holy Living and Holy Dying. Much of his writing was said to have been done on an island in the Lough.