Stephen’s uncertainty toward his mother

“A dim antagonism gathered force within him and darkened his mind as a cloud against her disloyalty: and when it passed, cloudlike, leaving his mine serene and dutiful towards her again…” (p. 178).

The beginning of chapter 4 consists of Stephen guiding himself through the church and his beliefs.  As he starts to think more about his potential involvement in university, his thoughts rapidly shift to anger towards his mother.  But as soon as the thought starts, it ends right at the end of the sentence and there is nothing more towards that in this passage.