Biel’s notion of the nature of the will, the formal and material cause of free will, and the relation between the will and sensory strivings, the intellect, grace and the will of God as the highest rule of the moral order, has been exhaustively studied on the basis of his explicit comments on the subject in the Collectorium. The current article attempts to determine Biel’s view of the intellect, the will, and memory on the basis of a close reading of the text of Canonis Missae Expositio alone. It examines the precise words Biel uses when reflecting on these faculties. Furthermore, the functions or defects that he implicitly assigns to them are also taken into consideration since they reveal what importance he affords to a particular faculty in the process of formation towards God, a process that is his objective in explaining the Roman Canon and the Mass’ prayers to God. The article demonstrates that, whereas Biel is optimistic about the power and possibilities of free will in the Collectorium, in the Canonis Missae Expositio he mainly emphasises the tendencies within and outside homo viator that weaken and wound the human faculties, mentioned above. More than the other faculties Biel views memoria as a ‘purification system’, because memory lies at the basis of purification of the mind and is the place where man becomes ardent in his love for Christ.