“You have asked me what I would do and what I would not do. I will tell you that I will do and what I will not do. I will not serve that in which I no longer believe whether it call itself my home, my fatherland or my church: and I will try to express myself in some mode of life or art as freely as I can and as wholly as I can, using my defense the only arms I allow myself to use-silence, exile, and cunning.”
James Joyce, A Portrait of the Artist as a Young Man (New York: Oxford University Press, 2008), pg. 208
Through this passage, Stephen is essentially answering his own question on page 139 when he wonders why he had refused to enter the clergy as intended. The answer is finally revealed in this passage.