Next year he was ordained to the curacy of St Mary's, Bryanston Square, and took priest's orders in 1868.
He afterwards added to his charge at Sparkford, Lovington, South Barrow and North Barrow, and in September 1782 was presented to the perpetual curacy of South Barrow by the Rev. John Hughes, Coln St Denys.
He took orders in 1874 and held a curacy at Dartford, in Kent, till 1877, when he became resident chaplain and private secretary to Dr Tait, archbishop of Canterbury, a position which he occupied till Dr Tait's death, and retained for a short time (1882-1883) under his successor Dr Benson.
One of his most intimate friends was William Stukeley (1687-1765) with whom he studied anatomy, chemistry, &c. In1708-1709Hales was presented to the perpetual curacy of Teddington in Middlesex, where he remained all his life, notwithstanding that he was subsequently appointed rector of Porlock in Somerset, and later of Faringdon in Hampshire.
He was ordained in 1834, and after a short curacy at Bubbenhall in Warwickshire was appointed chaplain of Guy's Hospital, and became thenceforward a sensible factor in the intellectual and social life of London.