[1] As a logician he was conservative, staying close to Aristotle and the Organon, and critical of the fashion for Ramism and its innovations.
[2] Crakanthorpe was, says Anthony à Wood, a great canonist, and so familiar and exact in the fathers, councils, and schoolmen, that none in his time scarce went before him.
Crakanthorpe seems to have been much influenced by John Rainolds, and became conspicuous among the Puritan party at Oxford as a disputant and preacher.
Wood describes him as a "zealot among them", and as having formed a coterie in his college of men of similar opinions, disciples of Rainolds.
He was also admitted, early in 1605, on the presentation of Sir John Leverson, to the rectory of Black Notley, near Braintree in Essex.
[3] The Defensio Ecclesiae Anglicanae, Crakanthorpe's best-known controversial work, was not published till after his death, when it was given to the world (1625) by his friend John Barkham, who also preached his funeral sermon.