Yevamot 42 - April 18, 17 Nissan

If chalitza was performed within the first three months after the husband’s death, the woman needs to wait three months before remarrying. Is it three months from the chalitza or from the death? What is the reason why all women need to wait three months before remarrying after death or divorce from their husband? The first explanation is that we want to be able to know who the son belongs to as God presents rests upon those who can trace their lineage. Rava says it is to prevent forbidden marriages – he brings four examples of issues that could arise, such as, marrying one’s sister without realizing. Also a convert needs to wait – why? The Gemara tries to figure out why a shorter time period would not have been sufficient. Why can’t we use other methods to determine whether or not the woman was pregnant? If we know she is pregnant, she still cannot get married as there is a different issue - that a man cannot marry a pregnant or nursing woman. Why is that prohibited? There were three opinions in the Mishna regarding which women need to wait three months before remarrying. According to which opinion do we hold? Rabbi Yochanan held like Rabbi Yosi who permitted women who were engaged to remarry, but it seems he changed his mind and required all women to wait three months. In what cases does Rabbi Yochanan hold like an unattributed opinion in a Mishna? What are the rules?