Mishnah Yevamot 5

¹Rabban Gamaliel says: There is no [validity] to a get given after a get, nor to a ma’amar after a ma’amar, nor to an act of sexual intercourse after another act of sexual intercourse, nor to a halitzah after another halitzah. However, the Sages say: There is [validity] to a get given after a get, and to a ma’amar after a ma’amar but not to an act of sexual intercourse after another act of sexual intercourse, or to a halitzah after another halitzah. ²How [is the release from yibbum effected]?If he performed ma'amar for his yevamah and gave her a get, she requires halitzah. If he performed ma'amar and and did halizah, she requires a get. If he performed ma’amar and then had intercourse with her, behold this is in accordance with the commandment. ³If the yavam gave her a get and then ma’amar, she needs [another] get and halitzah. If he gave her a get and then had intercourse with her, she needs [another] get and halitzah. If he gave her a get and then did halitzah, there is nothing after halitzah. If the yavam did halitzah and then he did ma’amar or gave her a get, or had intercourse with her; Or if he had intercourse with her and then did ma’amar, or gave her a get, or did halitzah, there is nothing after halitzah. [And the law is the same] whether there is one yevamah to one yavam or two yevamoth to one yavam. ⁴How is this so?If the yavam did ma'amar with this one and ma'amar with the other one, they need two letters of divorce and [one of them must have] halizah. If he did ma'amar with one and gave a get to the other, the [first one] needs a get and [one of them must have] halitzah. If he did ma'amar with one and had intercourse with the other, they need two gets and [one of them must have] halitzah. If he had ma'amar with one and gave halitzah to the other, the first needs a get. If he gave a get to one and a get to the other, [one of them] requires halitzah. If he gave a get to one and had intercourse with the other, [the second one] requires a get and [one of them must have] halitzah. [If he gave] a get to one and had ma'amar with the other, [the second] requires a get and [one of them must have] halitzah. [If he gave] a get to one and halizah to the other, there is nothing after halitzah. ⁵If he performed halitzah [for one] and then performed halitzah [for the other], Or performed halitzah [for one] and did ma'amar [with the other], or gave her get, or had intercourse with her; Or if he had intercourse [with one] and then with the other, Or had intercourse [with one] and then ma'amar with the other, or gave her a get, or performed halitzah there is nothing after halitzah. [There is no difference in the law] whether there was one yavam to two yevamoth or two yavamim to yevamah. ⁶[If the yavam] performed halitzah and then did ma’amar, gave her a get, or had intercourse with her; Or if he had intercourse with her and then did ma'amar, gave her a get, or performed halitzah, there is no valid act after halitzah,Whether [it was performed] in the beginning, in the middle, or at the end. Concerning intercourse, if it took place first there is no valid act after it; If it occurred in the middle or at the end there can be a valid act after it. Rabbi Nehemiah says: with both intercourse and halizah, whether it took place in the beginning, in the middle, or at the end, there is no validity in any act that follows it.