springs that are higher in the mountains than the Euphrates; how can their water come from the Euphrates? Rav Mesharshiyya said: These are ladders of the Euphrates, i.e., the waters of the Euphrates seep through the ground and are drawn upward to emerge from these springs.

The Gemara asks: But isn’t it written: “And a river went out of Eden to water the garden; and from there it was separated, and became four heads…And the name of the third river is Tigris; that is the one that goes toward the east of Ashur. And the fourth river is the Euphrates” (Genesis 2:10, 14)? This indicates that the Euphrates, which is mentioned last, is the least of the four rivers, not the source of the other three.

Rav Naḥman bar Yitzḥak said, and some say it was Rav Aḥa bar Ya’akov who said: It is the Euphrates that the verse mentions initially as the river that went out of Eden, which divided into all the other rivers. After the other three branched out from it, the Euphrates continued to flow.

It is taught in a baraita that Rabbi Meir says: Yuval is the name of the Euphrates River where it emerges from Eden, as it is stated: “For he shall be as a tree planted by the waters, and that spreads out its roots by the river [yuval], and shall not see when heat comes, but its foliage shall be luxuriant; and shall not be anxious in the year of drought, neither shall cease from yielding fruit” (Jeremiah 17:8). And why is it named Euphrates [perat]? Because its waters are fruitful [parim] and multiply without the need for rainfall.

The Gemara adds that this supports the opinion of Shmuel, as Shmuel says: The river is blessed from its riverbed; the additional water in the river is not from rainfall but rather from subterranean sources. And this statement disagrees with the opinion of Rav, as Rav Ami says that Rav says: When rain falls in the West, Eretz Yisrael, the great witness attesting to that fact is the Euphrates, as the water flow in the Euphrates increases after the rainy season.

The Gemara relates that Shmuel’s father fashioned a ritual bath for his daughters during the days of Nisan, and placed mats in the Euphrates River during the days of Tishrei when his daughters immersed in the river. He fashioned a ritual bath during the days of Nisan, because he holds in accordance with the opinion of Rav, as Rav Ami says that Rav says: When rain falls in the West, the great witness attesting to that fact is the Euphrates. Shmuel’s father was concerned that perhaps the rainwater and snow water that fell and accumulated in the river would exceed the amount of naturally flowing spring water that originated in the river’s sources, and the flowing rainwater would be the majority. Rainwater purifies only when it is collected; it does not purify when it is flowing. Therefore, Shmuel’s father fashioned ritual baths of standing water for his daughters.

And he placed mats during the days of Tishrei, when his daughters immersed in the river itself, to give them privacy. During Tishrei the waters of the Euphrates do not come from rainwater; rather, the waters are from the river itself, and therefore immersion is valid even when that water is flowing.

The Gemara notes: And this statement of Shmuel’s, that the additional water in the Euphrates is not from rainfall but from subterranean sources, disagrees with another ruling that he himself issued. As Shmuel says: Waters purify when flowing, i.e., when they are not collected into a ritual bath, only in the Euphrates during the days of Tishrei. Since rain does not fall in the summer, only after the summer, in Tishrei, is it clear that the water one is immersing in is in fact river water.

MISHNA: One who purchases an animal or has an animal that was given to him as a gift is exempt from separating animal tithe.

GEMARA: The Gemara asks: From where is this matter derived? Rav Kahana says that the verse states: “You shall not delay to offer of the fullness of your harvest, and of the outflow of your presses. The firstborn of your sons you shall give to Me. So you shall do with your oxen, and with your sheep: Seven days it shall be with its mother; on the eighth day you shall give it to Me” (Exodus 22:28–29).