17 – Seeing the New Moon

[23] The Ridbaz (1:341) writes thatit primarily depends on the ability to derive benefit from its light, and many Acharonim cite his words, including the Magen Avraham and Mishna Berura 426:3. However, the Chida writes in Moreh BeEtzba (184) that one may not recite the blessing even if the moon is covered only by a very thin cloud, and the Ben Eish Chai (Shanah Bet, VaYikra 23) concurs. Nevertheless, according to the letter of the law, it seems that all agree that one may recite the blessing as long as one benefits from the light. This is the conclusion of the Yalkut Yosef 426:5.

The Eshel Avraham of Buchach explains that one may recite the blessing if the light of the moon allows one to see most of the things that are usually visible when the moon is unobstructed. This is assessed based on the moon’s light on the seventh night of the month, or the fourth of the month, if there is a pressing need. In his opinion, one may recite the blessing towards the middle of the month even if the moon is covered by a thicker cloud, and one may recite it towards the beginning of the month only if the cloud is very thin. The poskim, however, seem to indicate that the distinction depends on the thickness of the cloud, not the day on which the blessing is recited. So writes the author of Sefer Kiddush Levanah 2:3 (with notes). Therefore, in my humble opinion, it seems that if one can see the outline of the moon, it is considered “visible” (possibly even according to those who are meticulous), and the blessing may be said.

According to the letter of the law, though, the halachah follows the opinion of the Ridbaz and the Eshel Avraham. This is apparent from the words of the Terumat HaDeshen quoted in Leket Yosher: “Once, he saw only a small portion of the moon, because it was partially covered by a cloud, and he nevertheless sanctified [it].”

Some say that one should look at the moon only briefly. See Mishna Berura 426:13 and Kaf HaChaim 34.

Many authorities write that one who recited the blessing without looking at the moon has fulfilled his obligation, as long as he could have seen it had he looked (see Sefer Kiddush Levanah 2:11). They derive this by logical inference from [the law of] a blind man. Most poskim hold that a blind man must say Birkat HaLevanah, because the blessing was instituted in recognition of the renewal of the moon. In addition, even the blind benefit from the moon in that others use its light to escort them. This is the viewpoint of the Rashal, Magen Avraham, Eliyah Rabbah, and Pri Chadash. However, the Maharikash holds that a blind man should not recite the blessing, for he does not derive pleasure from the moon. In practice, a blind man should not recite the blessing, because of the uncertainty surrounding the matter. It is preferable for him to hear the blessing from someone else (see Mishna Berura 426:1; Biur Halachah, s.v. nehenin; Kaf HaChaim 2).

[24] See Sefer Kiddush Levanah (chap. 2, n. 9) where the author quotes Rav Pe’alim (vol. 3, Orach Chaim 68) who is unsure how to rule in a case where the moon will disappear in the middle of the blessing, but no days remain on which to recite Birkat HaLevanah. He concludes, “It is possible to say that under such dire circumstances everyone agrees that one should say the blessing, but further investigation is required.” The author of Halichot Shlomo (Tefillah 15:12) writes that if one is concerned that immediately after beginning the blessing, the moon will be covered, it is permissible to say the blessing, b’diavad.