Christopher Hill has a chapter on the contrast between the Puritans who valued preaching highly, and sectors of the established Church that did not. He says:
One of William Prynne’s rare jokes was made in reply to Laud’s taunt that he could not have written Histriomastix single-handed. “It may be their [the bishop’s] laborious preaching once or twice a year permits them not to read or study half so much as meaner men.”
This was because some priests did not preach, they only read homilies or conducted prayers. Some bishops preached even less, so Prynne is attributing his knowledge to his studies in sermon preparation, something Laud (he implies) did not do. Hill continues:
Lord Brooke in 1642, after accusing some of the bishops of Arminianism and Socinianism, could rely on raising an easy laugh by saying that this was evidenced by their writings, “yea and sermons, though these be very rare.” It was a common jest in Dublin in the sixteen-thirties that the archbishop had only one sermon, on the text “Touch not mine Anointed” – “which once a year he commonly read” on the King’s birthday. His congregation knew it by heart.