Celia can be easily seen as an exceptional progressing character who has learned the value of her spiritual reality. She has succeeded in surpassing the ordinary and reaching a higher state of sublimation and salvation.
At the beginning of the play Celia was seen as a woman happy to be involved in adulterous relationship with Edward. She engaged in social conversations and seemed dynamic enough to talk to everyone and to argue with Edward. Celia was appalled at Edward thinking that she had 'taken' Peter. She was also spontaneous and honest to remark on the unidentified guest being the devil. Her private affair gave her the personality she needed; she wanted love and attention and Edward wanted sexual fulfillment, so they existed for each other's interest. Thus, she is obviously a happy, lively socialite. This seems an account of the character of Celia in the early phase of her life.
The second and most critical phase in her life is concerned with Edward's abandonment of her, learning that Lavinia has left Edward she immediately assumes that he will marry her, she doesn't have moral hesitations and doesn't seem to care what society might think of her. However, as it turned out Edward can't return her affections, and she was forced into a state of solitude; she became aware of the abyss she has been thrown into. Then suddenly she sees light and realizes that in Edward she was seeking something that was substantial to her and she must go on looking. In act one, she was explaining to Edward what she was feeling towards him and how she looked at him differently then. She was telling him of the thing she 'aspired to' that she thought was him. She said, "It must happen somewhere - but what and where is it?"
More revelations help sharpen Celia's recognition of her situation and the dilemma, which eventually wakes her to a condition where she has to make a choice. The conversation with Reilly discloses something of her background. We find out that her greatest affliction as she finds out to, is that of being alone and seeing no explanation as to why she shouldn't be. She views loneliness as an inexorable human condition. She is also seen to be concerned with 'a sense of sin' that she can't seem to define. Celia confesses to Reilly that she suffers from something 'stranger' than loneliness. She defines it as being abnormal to her and seems as if confused and searching for an answer. This conception of sin seems to be against her moral upbringing. Her understanding of sin revolves around the implication that sin is more than just doing wrong onto others. But her eventual decision to devote her life to God designates her notion of sin being detached from God. Celia feels driven by this sense of sin and the need to 'atone'. She has the-aspiration to be alleviated from this sense of loss after finding out that she hasn't achieved what she has been looking for in Edward.
Reilly points out that the cure is in her decision and so he proposes two ways towards her deliverance-this concludes Celia's development as a character. The first is to teach her to take on the human condition and this will allow her to live with her memory of the past and still maintain a daily routine. The other is a more courageous path and it involves an ongoing struggle with the self. It is a demanding quest for self-realization and for achieving peace within oneself. Celia chooses to take the role of savior, of discovering oneself and of serving humanity, which shows her determination to be in touch with her soul and her courage to give up physical indulgences. Celia is happy and sure that she herself took the decision, which gives significance to this choice. She says to Reilly before leaving, "But I know it is I who made the decision."
Celia's spiritually rooted choice is the way of the saints; she is expressing repentance for sin and demanding her penance. She shows valor to accept her sinning present and optimism to want to 'atone'. She has transcended the mediocre and reached out of herself. She has chosen to yield her individual will to the collective will of humanity. Celia has risen above her situation and her past reality and has chosen a path of self-awareness and of union with God.
Celia, indeed, has distinguished herself from the rest of the play's characters by outstanding characteristics of knowing one's needs and working for a self-satisfying future. She achieved self-knowledge and had her future clear in front of her. She conquered her present situation and dilemma and chose how to lead her life. She progressed in a state of mediocrity to a state of sublimation. Celia has proven to be a developing character through out the play whom T.S. Eliot had given the opportunity to exalt.