Seeing the full picture
ואם-פרוח תפרח הצרעת בעור וכסתה הצרעת את כל-עור הנגע מראשו ועד-רגליו לכל-מראה עיני הכהן
If the tzra’as spreads on the skin and the tzara’as covers the entire skin, from his head to his feet, the full view of the Kohen
This week’s double parsha mostly deals with the laws of tzara’as, most commonly translated as leprosy. While being a whitish skin condition, in reality it’s a totally unrelated spiritual malady with physical symptoms. Chazal tell us that someone who contracts tzara’as, known as a Metzora, usually committed a certain sin. One example is that of loshon hara, evil speech. As a result of his sin, he is infected with a disturbing skin condition, and has to have his status established by a Kohen. If the Kohen determines he is spiritually pure, then he is. The opposite is also true.
When discussing a specific case of how the tzara’as affliction spread, the Torah emphasizes the fact that the affliction filled the entire view of the Kohen. Our Sages learn from here that a Kohen who is blind in one eye, or has dimmed vision in both of his eyes, is disqualified from ruling on matters of tzara’as afflictions. Once we are taught this, the Tiferes Yisroel, written by Rav Yisroel Lifschitz (1782-1860) discusses the possibility of wearing eyeglasses. As stated, a Kohen whose vision has deteriorated cannot rule on tzara’as. What if he was wearing glasses, and can now see clearly? Is that permitted? Or perhaps that’s not called “the full view” of the Kohen, for something is “in the way” of his view. Do we have any precedent?
The Tiferes Yisroel indeed finds many cases that seem to indicate that wearing glasses should not interfere with his halachic sight requirements. For one, we have a rule that someone isn’t allowed to look at exposed intimate body parts while reciting words of prayer or Torah. What if the person is viewing this exposed skin through a glass, or a window? The halacha remains the same. We see then that seeing through glass is still called “seeing”.
Although, perhaps one could argue that we say to be stringent with regards to seeing through glass, and thus one shouldn’t recite words of holiness in such a case. However, to be lenient, such as ruling on tzara’as that the person is pure, maybe we have no precedent. To this, the Tiferes Yisroel says no. We have an example of even being lenient with regards to seeing through glass. He brings one authority who rules that if semi-transparent wax falls on a Sefer Torah, and it’s Shabbos where one cannot remove the wax, if the letters underneath the wax are still visible, one may read from this Sefer Torah. Their source is the above ruling that seeing exposed body parts through glass is still called seeing. We see then that we rule this way even to be lenient. Furthermore, the Tiferes Yisroel adds, we see all the time that people wearing glasses will make a blessing on the Torah reading and read from the Torah. It must be the case then that seeing through glass shouldn’t be a problem, and if it improves one’s vision, it should work even with tzara’as.
The Tiferes Yisroel then brings other precedents to be lenient. We find a couple of other cases where we make blessings, despite seeing something through glass. Saturday night, after Shabbos, we make a blessing on a candle. One can make this blessing even if the candle is in a glass container. As well, when we make a blessing on the moon at the beginning of the month, one can make it even while staring through a window. Even though some are careful to open the window if they can’t go outside, that’s just an extra level of caution, notwithstanding that the halacha would allow seeing it through glass. The Tiferes Yisroel concludes that regarding all blessings related to sight, no one cautions against making the blessing while wearing glasses, so it shouldn’t be a problem.
However, despite the above, the Tiferes Yisroel concludes that ruling on matters of tzara’as has a higher standard. There’s room for concern that if one views tzara’as afflictions through glass, the details of the affliction might be distorted, and the Kohen might rule incorrectly. He brings a precedent for this type of concern from the sanctification of the New Moon. Two witnesses are required to testify to the High Jewish Court when they first see the moon after the new cycle begins. Upon verifying their testimony, the court sanctifies the moon by declaring that the new month has begun. Regarding this testimony we are taught that if they witnessed the moon through glass, their testimony is disregarded. We are concerned they made a mistake in what they saw. He concludes that although he doesn’t have a definitive source regarding tzara’as, it makes sense to equate the two cases and disqualify the use of eyeglasses here as well.
However, the Shevus Yaakov, written by Rav Yaakov Reisher (1670-1733), makes an important observation. If we analyze the cases the gemarra discusses regarding the sanctification of the New Moon, we’ll notice that they’re all describing the inaccuracies of reflections. For example, the gemarra disqualifies witnessing the New Moon in the reflection in the water. As such, when it also disqualifies seeing through glass, it would be reasonable to say it means seeing the New Moon through a reflection in a mirror. Indeed, this seems to be the Rambam’s understanding. As such, we have no precedent to say that seeing with glasses is a problem, even when precision is required. We should then say that a Kohen wearing glasses is fit to rule on matters of tzara’as.
 Based on a shiur given by Rav Tzvi Berkowitz of Ner Yisroel, available here: https://nirc.edu/tazriametzora5781/
 Leviticus 6:2
 See Mishneh Torah Hilchos Tumas Tzara’as 16:10
 Arachin 16; Vayikra Rabbah 16:1
 מצורע, a contraction of מוציא שם רע, someone who causes a bad name (Arachin 15b)
 Besides loshon hara, the consensus is that murder and haughtiness cause tzara’as (ibid). Arachin 16a adds oaths in vain, illicit relations, theft and stinginess to the list, whereas Vayikra Rabbah loc. cit. cites lying, thinking about sins, running to do sins, and giving false testimony (citing Proverbs 6:17-19 as the source)
 Negaim loc. cit.
 Tosafos Yom Tov ad. loc., for if the Mishnah meant just one, there’s no need to mention being blind in one eye, as that’s obvious
 Tiferes Yisroel Boaz § 4 to Negaim 2:3
 Berachos 25a
 Halachos Ketanos 1:99, by Rav Yaakov Chagiz. For some reason the Tiferes Yisroel refers to this work as the Teshuvos Leket. I could hear that הלק”ט is short for הלכות קטנות, but not תשובות לקט
 The Tiferes Yisroel is focusing on whether the glass is considered an interruption in what I’m seeing, or not. He doesn’t seem bothered by the fact that eyeglasses are improving your vision. Rav Tzvi Berkowitz points out that the discussion of the Halachos Ketanos is purely whether the wax is considered an interposition in my sight or not. If so, one could argue it’s not a proof towards the question of eyeglasses, which without which a person can’t see what they’re trying to see. What’s clear is the Tiferes Yisroel, as well as the Shevus Yaakov below aren’t bothered by this difference between glass and eyeglasses. The latter however does note that one could argue that seeing through glass should be fine if one can hypothetically see without the glass, like the sevara of kol harauyah lebilah (Menachos 103b), unlike one who needs glasses, but in the end he is lenient
 The Tiferes Yisroel cites what he writes in his commentary to Shabbos Kalkalas Shabbos § 33
 Magen Avraham to Shulchan Aruch Orach Chaim 288:20
 Ibid to ibid 426:1 § 1
 Maharshal brought by ibid § 14
 Cf. Teshuvos Devar Shmuel § 242, who the Tiferes Yisroel does admit disagrees and is stringent (albeit out of doubt) with seeing through glass. He equates testifying about the new moon with blessing the new moon, which, as we’ll see, the Tiferes Yisroel sees as having different standards
 Rosh Hashanah 24a. This is the source which the Devar Shmuel used to justify his stringent stance even regarding blessing the New Moon
 He tries to bring a proof from a Tosefta (which I can’t find) but then admits it’s not foolproof
 Shevus Yaakov 1:126
 Mishneh Torah Hilchos Kiddush HaChodesh 2:5
 The Shevus Yaakov brings a final proof from the fact that the elders of the city have to witness the chalitzah process and observe in detail the procedure. Most elders require reading glasses, yet we’ve never seen anyone protest the participation of elders who can’t see without them. Rav Tzvi Berkowitz noted that this is a very interesting type of proof