The Christian Cabala, a Christianised version of Jewish mysticism originating in Renaissance Italy, reached England in the early sixteenth century and was met with a variety of responses from English Catholics in the Reformation period. While ‘cabala’ was used as a slur by both Protestant and Catholic polemicists, Robert Persons drew positively from the work of the Italian cabalist Pietro Galatino, and in 1597 Sir Thomas Tresham, then a prisoner at Ely, described in detail a complex cabalistic design to decorate a window. While the Christian Cabala was only one source of inspiration for Tresham, he was sufficiently confident in his cabalistic knowledge to attempt manipulations of names of God in his designs for the window at Ely and to insert measurements of cabalistic significance in the gardens on his Lyveden estate. Persons’s and Tresham’s willingness to draw on Christian cabalism even after its papal condemnation suggests the intellectual independence of English Catholics, who were prepared to make use of esoteric traditions to bolster their faith. The evidence for experiments with cabalism by a few English Catholics highlights the need for further re-evaluation of the significance of esoteric traditions within the English Counter-Reformation and the eclectic nature of post-Reformation English Catholic mysticism.