I had once vowed that I would never call her aunt again: I thought it no sin to forget and break that vow now. My fingers had fastened on her hand which lay outside the sheet: had she pressed mine kindly, I should at that moment have experienced true pleasure. But unimpressionable natures are not so soon softened, nor are natural antipathies so readily eradicated. Mrs. Reed took her hand away, and, turning her face rather from me, she remarked that the night was warm. (Jane Eyre)
Are the two past perfect because of the past tenses below, or because of some other reasons?
(Past tense)--------------------(the past of the Past tense) I thought it no sin-------------I had once vowed Mrs. Reed took her hand away----My fingers had fastened