In 1743 he was appointed by Sir Nathaniel Curzon to the perpetual curacy of St Mary Magdalene's Church, Clitheroe, Lancashire.
[4] In 1770 Fletcher Norton, now a successful lawyer, was elected Speaker of the House of Commons and invited King to be his chaplain and, two years later, to take up the post of vicar of St Mary’s and Holy Trinity in Guildford.
In 1774 King resigned his Guildford living when he was appointed to the third stall in St George's Chapel, Windsor Castle, and to the rectory of Dunsfold.
His youngest son, John King, was Under-Secretary of State at the Home Department from 1792 to 1806 and Secretary to the Treasury in Lord Grenville's administration in 1806.
A portrait of King's wife, Ann, painted by James Northcote in 1789, was sold by the same descendant to the Huntington Library in Los Angeles.