Overall in the novel Portrait, religion is depicted as an overbearing burden which clouds and heavies the mind and conscious while assuming power over its believers.
From early on in his life, religion hinders Stephen and his desires. At the beginning of the novel Stephen likes a young girl and thinks of marrying her later in life. His mother finds this completely wrong due to the fact that the girl's family is Protestant, and not Catholic like Stephen's family. As Stephen grows up, especially being in Catholic schools for his whole education, his religion continues to incessantly impede on his own thoughts, aspirations, and artistic abilities. From this we can infer that James Joyce himself was not a great supporter or fan of religion and that he felt no need for it.
As the novel progresses, so does Stephen's relationship with the Church. As a young boy he feels very in touch with a love for the Church. Slowly, while Stephen grows up, finds more of himself, and forms his own views, he begins to steer away from the Church. Thought at times during his development he returns to religion, Stephen still pulls away from the Church fairly steadily. The Church loses its grasp on him and he realizes the need to draw away from the Church in order to be himself and to go on with his life. By the end of the novel Stephen has given up on his religion and the Church and decided to go off on his own and leave it all behind. He believes in living his own life free from the society's affliction, as an artist.
Despite Stephen's lack of piety, he still contemplates becoming a Priest, as on page 161. Stephen's relationship with the Church is almost dependent. Even though he knows that it hinders him, he continues to feel like his life should encompass the Church. But, he declines the offer to join the Jesuits so that he can study at the university. During the middle of the novel Stephen constantly switches from embracing the Church and his religion to renouncing it and living in sin and back again. Joyce on the other hand believes that the Church is on of the three things holding the Irish down. Joyce's beliefs were that the Church has no need in the life of the Irish and that it cannot truly help them no matter what.