 In 1694 Clifford published 'The Catechism, containing the Principles of Christian Religion,' together with 'A Preparation Sermon before the receiving of the Holy Sacrament of the Lord's Supper,' preached at Serjeants' Inn Chapel in Fleet Street.Clifford was twice married.His first wife's name is unknown, but on 30 May 1667 he obtained a license for his marriage at St. Dunstan in the West, or the chapel of Serjeants' Inn, with Clare Fisher of the parish of St. Gregory by St. Paul's.