Kiddushin 60B

מאי בינייהו? איכא בינייהו שנתקרע הגט או שאבד, לרב הונא הוי גט, לרב יהודה לא הוי גט.

What is the difference between the explanations of Rav Huna and Rav Yehuda? Even Rav Huna agrees that she cannot marry someone else until she gives him the money. Until that point the bill of divorce does not come into effect and she remains married to the first man. The Talmud answers: The difference between them is in a case where the bill of divorce was torn or lost after she received it but before she gave him the money. According to the opinion of Rav Huna it is a valid bill of divorce, as the divorce takes effect from the moment he gives her the document. According to the opinion of Rav Yehuda it is not a valid bill of divorce, as he maintains that the bill of divorce goes into effect only later, which is impossible as it is either torn or lost.

וצריכא, דאי אשמעינן גבי קידושין, בהא קאמר רב הונא, משום דלקרובה קאתי, אבל גירושין, דלרחוקה קאתי, אימא מודי ליה לרב יהודה.

The Talmud comments: And it is necessary to state both disputes, the one with regard to betrothal and the one with regard to divorce, as neither halakha could be derived from the other. As had it taught us only that the two rabbis disagree with regard to betrothal, one might have said that it is there that Rav Huna says that the betrothal takes effect immediately, despite the fact that he must still give her the money, because betrothal comes to draw her near to him. Therefore, it is likely that he meant for the betrothal to take immediate effect. But with regard to divorce, when he comes to distance her, you might say that Rav Huna concedes to Rav Yehuda that the divorce comes into effect only from the moment she gives him the money.