He believes that a virgin like the Lady is secure or safe from the violent attacks imagined by his younger brother.

他认为像那位女士那样的处女，在他弟弟想象的,暴力袭击中是很安全的。

耶鲁公开课 - 弥尔顿课程节选

So notice first here that the younger brother compares his sister's virginity to a miser's treasure.

所以首先注意这个小哥哥,他将妹妹的贞节与吝啬鬼的财富作比较。

耶鲁公开课 - 弥尔顿课程节选