there is no need for the verse to teach this. After all, if this drop of ziva causes impurity for others, i.e., if the person emitting the drop imparts impurity through carrying, is it not all the more so that the drop itself imparts impurity through carrying? Rather, it is obvious that the verse is referring to a drop of ziva from a zav who is also a leper. And it was necessary for the verse to teach this halakha, as it could not be derived by means of the a fortiori inference. This is because this drop of ziva is not what causes the leper to impart impurity through carrying; rather, it is his leprosy that causes him to impart impurity through carrying.

Rava concludes: And as the verse mentions the word “issue” twice, it is evident that it is referring to a second sighting of ziva. From the fact that a verse was necessary to include a second sighting of ziva of a leper, teaching that his ziva imparts impurity through carrying, conclude from it that the place of ziva is not considered a source. If it were a source, then even the first sighting of ziva would impart impurity through carrying.

Rav Yehuda of Diskarta said to Rava: From where do you know that the verse is referring to a zav who is also a leper? Actually, perhaps I will say to you that the verse is referring to the ziva of one who is just a zav. And as for that a fortiori inference that you said: If this drop of ziva causes impurity for others, is it not all the more so that the drop itself imparts impurity through carrying, one can counter that inference. The case of the scapegoat brought on Yom Kippur will prove that this a fortiori inference is not valid, as it causes impurity to others, since the dispatcher of the scapegoat is rendered ritually impure, and yet the goat itself is pure, as a living animal cannot be rendered impure.

With regard to the dilemma raised by Rav Yosef about the first sighting of ziva of a leper, Abaye said: What is the reason he raises such a dilemma? But it was he who said that when the verse states: “This is the law of the zav” (Leviticus 15:32), it thereby teaches that the halakhot of a zav apply whether he is an adult or whether he is a minor. And since he derives this halakha from there, the verse: “And of them that have an issue [vehazav] of ziva, whether it be a male or a female” (Leviticus 15:33), remains available for him to derive as follows: “Whether it be a male” serves to include a male leper with regard to his sources of bodily emissions, and “or a female” serves to include a female leper with regard to her sources of bodily emissions.

And as this verse discusses a full-fledged zav, and the word “issue” is mentioned twice, the Merciful One compares a leper to a full-fledged zav: Just as a full-fledged zav imparts impurity through carrying, so too, the first sighting of ziva of a leper imparts impurity through carrying.

§ Rav Huna says: The first sighting of ziva of a zav imparts ritual impurity to one who comes into contact with it, even if the emission occurred due to circumstances beyond his control, as it is stated: “This is the law of the zav, and of him from whom the flow of seed goes out” (Leviticus 15:32). The verse compares the first sighting of ziva to a seminal emission: Just as semen imparts impurity even if it occurs due to circumstances beyond his control, so too, the first sighting of a zav imparts impurity even if it occurs due to circumstances beyond his control.

The Gemara analyzes the statement of Rav Huna: Come and hear a mishna (Zavim 2:2): With regard to a man who saw a first sighting of ziva, one examines him to determine whether the discharge was caused by circumstances beyond his control. What, is it not that the purpose of this examination is to clarify that he does not have ritual impurity, i.e., if the discharge was due to circumstances beyond his control he remains pure, which contradicts the statement of Rav Huna? The Gemara responds: No, the purpose of this examination is to determine whether he will be obligated to bring an offering if he experiences another two discharges of ziva. If the first sighting was caused by circumstances beyond his control, it is not counted toward the three sightings that render one liable to bring an offering.

The Gemara suggests: Come and hear the latter clause of the same mishna: When he experiences the second sighting of ziva, one examines him to determine whether the discharge was caused by circumstances beyond his control. For what purpose does one examine him? If we say that it is to exempt him from bringing an offering in the event that he experiences a third discharge but not to clarify that he does not have ritual impurity, this is untenable, as one may read here the verse: “An issue out of his flesh” (Leviticus 15:2), from which it is derived that one is not rendered a zav if the discharge occurred due to circumstances beyond his control. Rather, is it not that the examination serves to clarify that he does not have ritual impurity? And from the fact that the examination in the latter clause is for purposes of impurity, one may conclude that the examination of the first clause is also for purposes of impurity.

The Gemara rejects this: Are the cases comparable? This case is as it is, and that case is as it is. In other words, it is possible that each examination is intended for a different purpose. In particular, the first examination is meant to exempt him from bringing an offering, and the second examination pertains to both the offering and ritual impurity.

The Gemara suggests: Come and hear the same mishna, which states that Rabbi Eliezer says: Even after the third discharge one examines him, because of the offering. In other words, if the third discharge occurred due to circumstances beyond his control, he is not liable to bring an offering. From the fact that according to Rabbi Eliezer the examination is due to the offering, one may conclude by inference that the first tanna is saying the examinations are for ritual impurity. If so, then according to the mishna one who has an initial discharge of ziva due to circumstances beyond his control remains pure.

The Gemara rejects this suggestion: No, this is not the proper explanation of the mishna. Rather, everyone agrees that the examination serves to exempt him from bringing an offering. And here they disagree with regard to whether one interprets instances of the word “et” in a verse. With regard to a zav, the verse states: “And of them that have an issue of ziva [vehazav et zovo], whether it be a male or a female” (Leviticus 15:33). The Rabbis do not interpret instances of the word “et,” and Rabbi Eliezer interprets instances of the word “et.”

The Gemara elaborates: The Rabbis do not interpret instances of the word “et.” Therefore, they explain the verse as follows: “Hazav” is referring to one sighting; “zovo” makes two sightings, and when the verse states: “Whether it be a male,” this indicates that for the third sighting the Merciful One compares the halakha of a male to that of a female, i.e., just as a woman is rendered impure even through an emission of ziva due to circumstances beyond her control, so too, the third sighting of ziva by a man renders him impure even if it occurs due to circumstances beyond his control. Accordingly, the Rabbis maintain that there is no need for an examination after the third sighting.

And Rabbi Eliezer interprets instances of the word “et.” Therefore, he explains the verse as follows: “Hazav” is referring to one sighting; “et” makes two sightings; “zovo” totals three sightings. Accordingly, even for the third sighting of ziva one must examine whether it was caused due to circumstances beyond his control. If it was, he is not liable to bring an offering. When the verse states: “Whether it be a male,” this indicates that for the fourth sighting the Merciful One compares the halakha of a male to that of a female, in that it is counted as a sighting even if it occurred due to circumstances beyond his control.

The Gemara attempts to refute the statement of Rav Huna: Come and hear that which Rabbi Yitzḥak says: But wasn’t a zav included in the category of one who experienced a seminal emission? Why, then, was he taken out and discussed in a separate passage? In order to be lenient with him and to be stringent with him relative to the halakhot of one who experienced a seminal emission. Rabbi Yitzḥak elaborates: The separate passage serves to be lenient with him, as he is not rendered impure through an emission that occurs due to circumstances beyond his control, unlike one who experienced a seminal emission. And the separate passage serves to be stringent with him,