He has been noted as "an inveterate enemy of the Jews",[2] and his demands that they be expelled from England were cited in the evidence presented for his canonization.

[7] On 25 February 1264, when he was Archdeacon of Stafford, Cantilupe was made Lord Chancellor of England,[8] but was deprived of the office after de Montfort's death at the Battle of Evesham, and lived abroad for a while.

[12] Cantilupe was now a trusted adviser of King Edward I and when attending royal councils at Windsor Castle or at Westminster he lived at Earley in Berkshire.

He then demanded that any unconverted Jews should be expelled from the Kingdom as “enemies of God and rebels against the faith” (inimici Dei et rebelles fidei), threatened to resign and broke down in tears.

Supporters of his cult included Edward I, who attended the ceremony to translate Cantilupe's body to its new position in 1287, seen as a step towards confirmation of his sainthood.

[18] One of the many miracles cited in his cause of canonization was the supposed raising from the dead of William Cragh, a Welsh rebel who was hanged in 1290, eight years after Cantilupe's death.

A papal inquiry was convened in London on 20 April 1307 to determine whether or not Cantilupe had died excommunicate, since this would have precluded his being canonized.

Forty-four witnesses were called and various letters produced, before the commissioners of the inquiry concluded that Cantilupe had been absolved in Rome before his death.

[20] His shrine became a popular place of pilgrimage, but only its base survived the Reformation until a new upper section (a feretory) was recreated in 2008[21] under the guidance of Nicholas Quayle.

[23] Architectural features of the Cathedral, which are also thought to relate to the cult, echo similar anti-Jewish themes, in particular Synagoga, a blindfolded Jew with a broken staff, dropping twin tablets of God's law.

The records associated with his canonisation have been the subject of academic investigation, leading to some reassessment, for instance looking at the process by which miracles were sought and attributed, to better comprehend how such reports were generated and understood at the time.

These emphasise his direct appeals for the expulsion of the Jews, and his refusal to socialise with women, believing this to be extreme even for his time; this includes reinterpretation of objects associated with his cult, such as the Mappa Mundi.