Catalina’s ability to transform herself into a man and live undetected for more than two decades suggests that gender is constructed, not innate, and that masculinity can be created. Throughout her memoir, from her teen years until her forties, Catalina builds up her masculine façade. She emphasizes only the qualities in herself that would be identified as traditionally masculine, and she omits any characteristics that would be deemed female. Catalina is no longer the victim of violence, as she was as a child and teenager; now she is combative and violent and kills many men. She is boastful and aggressive in a conventionally masculine manner, and her life as a soldier only reinforces these masculine traits. Her training as a warrior also helps her make decisions quickly, without weighing the consequences of her actions.
Her machismo is never more apparent than when she kills one of her fellow lieutenants for calling her a “cuckold,” that is, a man whose wife is sexually unfaithful. This is an insult that is designed specifically to be leveled at a man—and Catalina has embraced her masculine alter-ego so thoroughly that she is willing to kill to defend her male honor. In deciding to dress as a man, Catalina learns how much of traditional masculinity and violent behavior is a construct, for she makes herself into a bold and violent killer by the force of her own determination. After living as a man for more than two decades, there are almost no traditionally feminine characteristics apparent in Catalina’s personality.
Although Catalina’s relationship with God fluctuates throughout her life, she always sees religion and God as avenues to forgiveness, redemption, and, sometimes most important, rescue. Although Catalina does not appear to be particularly devout, religion infuses her character, and she often credits God for helping her out of tight situations. Yet Catalina turns to God only out of sheer desperation. She visits a church only when trying to escape arrest and imprisonment, and she gives thanks to God only in moments where her life is at risk. Her vision of God seems to be of a benevolent being who allows her to escape punishment for her crimes, which is why she often flees to a church or cathedral immediately after committing a crime, in order to escape retribution. Despite her unwillingness to write about her relationship with God except in crisis, Catalina’s religious beliefs are clearly integral to her character. Her belief that God is responsible for allowing her to escape punishment for her crimes relieves her of guilt and frees her to continue her criminal lifestyle.
Throughout Lieutenant Nun, disguise gives Catalina power. When she leaves the convent, clothing is her disguise and means of changing her gender identity. This disguise and the bravery that donning it requires are the most important factors in her escape, as well as in assuring her safety. Not only does her disguise allow her to camouflage herself as a man, but it also allows her to feel masculine enough to develop a male persona. As a teenager, Catalina explores whether her disguise will fool others. When neither her aunt nor her father recognize her, Catalina risks going back to the convent, where she eludes detection by her mother and, presumably, the nuns and novices with whom she had spent eleven years. Catalina clearly intends this return as a test to bolster her confidence, and she passes easily. Her attitude is as vital to her disguise as her clothing is. Catalina also uses a disguise to change more than just her sex. She changes identities when it suits her and gives false identification many times when being pursued by the law. Catalina views her external identity as fluid, and she uses this fluidity to her advantage.