He became in 1721 a chaplain to Lord-chancellor Thomas Parker, 1st Earl of Macclesfield, in 1724 vicar of St Olave, Jewry, and prebendary of Gloucester, and in 1729 vicar of Great Marlow also, without surrendering earlier preferments. In 1723 he was elected a Fellow of the Royal Society. In October 1752 he was appointed bishop of St. David's, and consecrated on 28 January in the following year. Ellys continued to hold his prebend and his city living in commendam, and went every Sunday morning in winter from his house in Queen Square to preach to his parishioners. He died at Gloucester on 16 January 1761, and was buried in the south aisle of Gloucester Cathedral.
