Martin's father was irked by Martin's lowly profession and the friars agreed with Don Juan that Martin, being lettered and well versed in medicine as well, should be received as a brother-professed.

But because of his humility Martin would not agree to become even a lay-brother, and he never rose above the degree of a donator, a tertiary. The only privilege to which, some fifteen years later, he joyfully assented was to be allowed to take the solemn vows for life whilst he remained a tertiary: this was indeed a rare privilege. During the whole of his religious life Martin wore a white habit with a black cappa or cloak.