Summary:
Generally a אנוס by a שבועה is פטור from עונש; however here the woman is at fault for not protecting the פקדון properly, realizing that she make come to take an improper oath.
Summary:
The חכמים did not want to administer an oath to an אלמנה because since she is מורה היתר, she may be severely punished; instead they made her take a vow. Nowadays we proclaim a חרם if she is lying.
This was not taught universally; only in בי"ד etc.- לא שנו אלא בבית דין
Summary:
רש"י (here) and תוספות agree that there is נקיטת חפץ both by a שבועה דאורייתא and a שבועה דרבנן (in בי"ד). The difference between a שבועה דאורייתא and דרבנן is in כיבוי נרות (and the different ramifications mentioned in מסכת שבועות).
And she vows and prohibits herself from fruits of the world that she did not receive from her כתובה, etc. - ונודרת ואוסרת פירות שבעולם עליה שלא קיבלה מכתובתה כולי
Summary:
A נדר which one cannot fulfill is a valid נדר to the extent that he receives מלקות for בל יחל. However he is immediately permitted in what he forbade himself. נדרי הבאי are permitted because he is exaggerating; however שבועות הבאי are prohibited, since the תורה writes לא ינקה, the חכמים were מחמיר. We will not accept a נדר שא"א לקיים as an assurance (since people are not that concerned of transgressing a one time איסור); they are concerned for a continuing prohibition.
