Bechoros Daf 50 בכורות דַף 50

The Mishnah on the previous Daf taught that the five סלעים of פדיון הבן (and other obligations written in the Torah) are paid in מנה צורי – Tyrian currency. The מנה צורי was made from pure silver, and was eight times the value of "כסף מדינה" – provincial currency, which contained copper mixed with silver.

Rava says: סילעים דאורייתא תלתא ותילתא הוי – Biblical סלעים are worth three and a third צורי dinars, unlike צורי selaim, which are worth four dinars. His source is the passuk "עשרים גרה השקל" – the shekel is worth twenty “gerah,” translated as twenty "מעין". Since a Baraisa values six silver מעה to be a dinar, a Biblical סלע (called a “shekel” in the Torah) is worth three and a third dinars (and thus worth twenty מעה). The Gemara objects: a Baraisa states that a סלע is worth 48 פונדיונין, equal to four צורי dinars (at twelve per dinar), not three and a third!? The Gemara answers that the Baraisa refers to בתר דאוסיפו עילוייהו – after they added on to [shekalim] and increased their weight to four dinars. A Baraisa darshens שאם רצה להוסיף יוסיף – if he wishes to add to the shekel's weight, he may add, from the word "יהיה" – [the shekel] "shall be" twenty גרה, implying additional possible “beings.”

Rebbe Oshaya said: ביקשו לגנוז כל כסף וזהב שבעולם מפני כספה וזהבה של ירושלים – [The Rabbis] sought to conceal all the silver and gold in the world because of the silver and gold which the Romans plundered from Yerushalayim during the חורבן and mixed into their own silver and gold, עד שמצאו לו מקרא מן התורה שהוא מותר – until they found a passuk in the Torah that it is permitted. The passuk says: ובאו בה פריצים וחללוה – and lawless people shall enter [the Mikdash] and profane it, indicating that when the idolators invaded the Beis Hamikdash, all its contents became chullin. The Gemara wonders: וירושלים הויא רובא דעלמא – is Yerushalayim the majority of the world? Why did they consider prohibiting all the silver and gold in the world? Abaye clarifies that Rebbe Oshaya originally said: בקשו לגנוז דינרא הדריינא טירייאנא שייאפא מפני טבעה של ירושלים – they sought to conceal every rubbed-out Hadrian and Trajan dinar because of the coins of Yerushalayim from which most of these coins had been minted, until they found a passuk permitting it.

Rav Assi said: כל כסף האמור בתורה סתם כסף צורי – Any “כסף” mentioned in the Torah without specification refers to Tyrian currency, ושל דבריהם כסף מדינה – and any “כסף” mentioned by the Rabbis refers to provincial currency. This statement is challenged from the law of kiddushin, for which Beis Shammai requires a minimum of a silver dinar, whereas Beis Hillel says a פרוטה is sufficient. Since the Torah required "כסף" for kiddushin, it emerges that Rav Assi’s statement accords with Beis Shammai (since כסף צורי did not have a פרוטה, which is made from copper)!? Therefore, Rav Assi’s statement is emended to read: כל כסף קצוב האמור בתורה – Any set amount of כסף mentioned in the Torah (such as five selaim for פדיון הבן) refers to Tyrian currency. Since kiddushin has no defined amount, a perutah is sufficient. The Gemara objects that our Mishnah already taught that all Biblically set amounts are calculated in מנה צורי, and answers that Rav Assi’s novelty was the second half of his statement, that Rabbinically mandated amounts are calculated in כסף מדינה.