In 1663 Clifford published the first edition of the work hy which he is best known, 'Divine Services and Anthems, usually sung in the Cathedrals and Collegiate Choires in the Church of England.'
This is a collection of words of anthems, and was originally intended only for use at St. Paul's, but in 1664 Clifford published a second edition, with large additions, so as to apply to 'all choirs in England and Ireland.'
The work contains the words of 393 anthems, besides tunes of chants, &c., 'Brief Directions for the understanding of that part of the Divine Service performed by the Organ in St. Paul's Cathedral on Sundayes;' a 'Scale or Basis of Musick,' by Dr. Ralph Winterton, regius professor of medicine at Cambridge, and a 'Psalm of Thanksgiving,' sung by the children of Christ's Hospital, set to music by Thomas Brewer.
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.
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.