New York (VINNEWS/Rabbi Yair Hoffman)

THE QUESTION

On Wednesday afternoon, the moon slid directly in front of the sun in a solar eclipse watched by over a million Americans. In other words, the sky itself announced the arrival of the new moon – the molad: Wednesday, August 12, at about 1:37 in the afternoon.

But the molad we had announced in shul was Thursday, August 13, at 1:15 in the morning — almost twelve hours later.

So when the Rema tells us to wait 72 hours after the molad before saying Kiddush Levana, which molad is he counting from? Counting from the real molad, the 72 hours are up on Shabbos afternoon. Counting from the announced molad, they are not up until 1:15 Sunday morning.

Can a person then bentch kiddush levana this Motzaei Shabbos at a decent hour, or not?  Inquiring minds want to know.

THE ANSWER

Let’s start with what the announced molad actually is. It is called the molad ha’emtza’i — the average molad. It is a fixed piece of arithmetic locked in when the calendar was set by Hillel the Second around 400ish or a bit before: 29 days, 12 hours, and 793 chalakim, every single month, forever. It was never designed to tell anyone where the moon really is.

The real new moon runs early some months and late others, sometimes by as much as fourteen hours in either direction. This month’s gap of about eleven and a half hours is completely ordinary.

So the question is what are the 72 hours measuring — the calendar, or the moon?

The TaZ answers this directly: v’lav b’yamim talya milsa ela me’eis shenehenin me’oram b’tov — it does not really depend on days at all, but on the point when a person can benefit from the moon’s light. The Mishnah Berurah says the same thing: shenehenin k’var me’orah. The three days are not a number with a life of its own. They are a rough stand-in for a physical fact — the moon has grown bright enough to be usable.

Benefiting from light is a fact about the sky, not about math. When a stand-in and the real thing disagree, and the real thing is sitting right there in plain view, the real thing should win.

By Motzaei Shabbos the moon will be about three days and seven hours old, roughly eleven to thirteen percent lit. No one can claim that light is not being benefited from. And there is no room to argue about the timing, because the eclipse was an observed event. It functions less like a cheshbon and more like eidus.

THE OTHER SIDE — WHICH IS NOT WEAK

The counter-argument is that the entire Jewish calendar now runs on the average molad. Rosh Chodesh, the yamim tovim, every yahrtzeit — all of it. The Rambam’s calculations of the true molad were written for a beis din taking testimony from witnesses, a system not currently operating. And “three days” is itself a deliberately rough number to begin with; the Mekubalim say seven, the Shulchan Aruch codifies seven, the Rema says three. Injecting astronomical precision into a number that was never meant to be precise is a strange move.

There is also a consistency problem. If the real molad governs in a month when it falls earlier, then in a month when it falls later shouldn’t we compensate when it falls later? This would push Kiddush Levana back an extra half-day past what everyone assumes. Very few people are prepared to live with that. A rule that only gets invoked when it makes things easier is not really being treated as a rule.

A SECOND MACHLOKES NOBODY MENTIONS

Also, in B’Shvilei HaMinhag, Rabbi Elyakum Dworkes observes that according to Shulchan Aruch (O.C. 426:2) we do not bentch levana except on Motzaei Shabbos, when a person is mevusam u’vegadav na’im — refreshed and in nice clothing.

But the Shulchan Aruch immediately adds a limit: this is only when Motzaei Shabbos falls before the tenth of the month. If Motzaei Shabbos would land on the eleventh or later, we do not wait for it — because maybe it will be cloudy for two or three nights straight, the moon will not be seen, and the zman will slip away entirely. That is the Rema, and the Magen Avraham (s.k. 3).

The logic underneath is a general rule worth knowing: when there is a real risk of losing a mitzvah completely, we do not delay it just to perform it in a nicer way. But when the only concern is the softer principle of mitzvah haba’ah l’yadcha al tachmitzena — don’t let a mitzvah go stale — that applies only if the later performance would be no better. If waiting produces a genuinely more beautiful mitzvah, waiting is permitted.

But not everyone agrees. There is a whole school of poskim who hold that one should not wait for Motzaei Shabbos at all — that as soon as three days have passed, a person should go outside and say Kiddush Levana, precisely so as not to let the mitzvah sit. This is the position of the Bach, and it is discussed in the Biur Halacha on siman 426, in Shu”t Shevus Yaakov (vol. 3, siman 34), in the Siddur Ya’avetz in Hilchos Kiddush Levana, and in Shu”t Beis Yaakov (siman 142), brought in Shaarei Teshuvah.

The Chacham Tzvi (siman 106) actually proves from a sugya in Yevamos (39) that a mitzvah may be delayed for the sake of doing it better.

How so?  The Gemara says yibum belongs to the oldest brother. If he refuses, we turn to the others. But if he says “wait until the oldest brother comes back from overseas,” we do not listen to him. The Nimukei Yosef explains that we refuse because of the danger that the mitzvah gets pushed off and never happens. The Chacham Tzvi asks: why did the Nimukei Yosef need to add the reason of iggun — leaving the woman stuck? The answer he draws out is that delaying for hiddur is normally acceptable; here it was the woman’s plight, not the delay itself, that forced the issue.

And why do we wait for Motzaei Shabbos in the first place? The Chesed L’Avraham Tinyana (O.C. 78) gives a striking answer. The takanah itself was built around Motzaei Shabbos, because that is when a person is in a state of joy. That is why the Maharil ruled that Kiddush Levana is not said on Motzaei Shabbos Chazon, and not before Yom Kippur — the awe of the coming judgment crowds out the simcha, and the Shechinah is received only through joy.

On that view, waiting for Motzaei Shabbos is not a delay at all. It is the mitzvah being done the way it was designed. The Haghos Maimoni records that the Maharam would put on a heavy, dignified cloak even on a weekday, in order to open his heart and bless with joy.

WHY THIS SETTLES THE PRACTICAL QUESTION

When these two positions meet this particular week – this is what happens:

The shita that says don’t delay — the Bach, the Shevus Yaakov, the Siddur Ya’avetz, the Beis Yaakov — want the bracha said at the earliest legitimate moment. On the real molad, that moment is Motzaei Shabbos.

The shita that says wait for Motzaei Shabbos — the Shulchan Aruch, the Rema, the Chesed L’Avraham — is pointing at Motzaei Shabbos.

Both roads lead to the same night. That is unusual, and it is worth noticing.

There is also a position quoted in the name of the Ya’avetz that if the 72-hour mark will arrive at any point during a given night, the bracha may be said earlier that same night. Sunday 1:15 a.m. falls inside the night of Motzaei Shabbos, which runs until alos. So even someone who insists on the announced molad has a recognized basis to bentch levana right after Shabbos.

THE PRACTICAL DETAIL MOST PEOPLE MISS

Also, a three-day-old moon does not stay up. It sets roughly two and a half to three hours after shkiah. In the New York area this Motzaei Shabbos, with shkiah near 7:55 p.m., the moon will likely be gone by somewhere around 10:15 to 10:45 p.m. — worth checking against a local table for the exact minute.

Which means the “just wait for the announced 72 hours” plan does not actually exist. At 1:15 Sunday morning there will be no moon in the sky to say a bracha on. The real choice is between saying it early Motzaei Shabbos or waiting until Sunday night.

The Rema’s own reason for not waiting past the tenth was the risk that the moon simply would not be available. Here the moon really is unavailable at the hour the strict reckoning points to.

BOTTOM LINE

There is solid ground to say Kiddush Levana this Motzaei Shabbos. The TaZ’s reason points to the physical moon. The eclipse establishes the true molad beyond any doubt. Seventy-two real hours will have passed by Shabbos afternoon. The Ya’avetz permits it independently even on the announced count. The Bach and those with him actively want it said at the first opportunity. And the Shulchan Aruch’s own preference for Motzaei Shabbos — mevusam u’vegadav na’im — together with the Chesed L’Avraham’s explanation that the joy of Motzaei Shabbos is the heart of the takanah, is a real reason to want it then rather than merely permission to have it then.

That said, sof zman Kiddush Levana this month is not until about August 27. Nobody is under pressure. Anyone who would rather not enter the machlokes at all can simply wait for Sunday night, when both reckonings agree and the moon stays up longer besides.

As always — ask your Rav.

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