Blood Moons and Their Signficance to Judaism

Usually, the moon has a pale white or yellowish color. But did you know that the moon can have other colors as well?

There’s also the “blue moon.” A blue moon is defined as the second of two full moons in a single calendar month, or the third of four full moons in a single season. Blue moons are not really blue, but they’re called that way because the photographs taken of them have special blue camera filters. When you hear someone say it’s “once in a blue moon,” you know that they mean it.

But how about a “blood moon”? It’s a layman term for the total lunar eclipse, which is called that way because of the moon’s reddish color. A lunar eclipse happens when the moon moves into the earth’s shadow. This natural phenomenon occurs when the sun, earth and the moon are closely aligned with each other, and only when there’s a full moon.

There are three types of lunar eclipse: total, partial, and penumbral. The total lunar eclipse is the most dramatic – and this is where the moon exhibits a distinctive reddish shade.

So why does the moon turn reddish during a total lunar eclipse?

It occurs when the moon travels the earth’s umbra and completely blocks all direct sunlight that illuminates the moon’s surface. But some of the sunlight still reaches the moon’s surface indirectly, by way of the earth’s atmosphere, giving the moon its reddish, yellowish, or orange-ish shade.

Most of us are excited to witness the blood moon, which is a fascinating natural and scientific phenomenon. However, it also incites doomsday fears and triggers apocalyptic predictions, especially among those who believe that blood moons are signs of bad things to come.

So how does a blood moon mean to the Jews?

Rabbinic Judaism views a blood moon in a similar manner – a sign of something bad to happen. According to Gemarah , an eclipse is a bad omen for all Jews, with some scholars extending the warning to include all mankind.

However, the Gemarah adds some assurance: when people perform God’s will, they will not need to fear such bad omens (Succah 29a).

Eclipses – solar and lunar – are easily predictable cosmological phenomena. In fact, even during the Talmudic era, people were able to predict these eclipses accurately. But nonetheless, why does an eclipse have any negative spiritual impression at all?

Many individuals and sectors have criticized these rabbinic sages, assuming that they merely copied the superstitions regarding eclipses that were once widespread during the ancient times.

But does it mean people from the ancient era were that ignorant? Despite the fact that superstitious beliefs regarding eclipses were prevalent during antiquity, it appears that astronomers at the time – both Jewish and non-Jewish – were able to correctly predict these celestial cycles. There are evidences of this. For example – the ancient clay tablets from the Babylonians and the Chaldeans describe how their priests were able to predict each eclipse accurately by studying the orbits of the moons and the planets.

Astronomy (and its branch cosmology) is also seen as important to rabbinic sages. The 2nd-century sage Eleazar Chisma believed that mathematics and astronomy were essential appendages to Torah study (Ethics of the Fathers, 3:23). In addition, the Gemarah states that there is a duty to calculate the planet’s orbits (Shabbat 75a).

Yohanan ben Zakkai, one of the important sages during the Second Temple era, studied astronomy and other secular fields. Other sages (such as the sages who established centers of learning following their exile from the Land of Israel) also professed a keen interest of the celestial spheres and their movements.

But despite these sages’ interest and knowledge in astronomy and their ability to predict celestial cycles, how could they attribute apparently superstitious significance to them?

The late Orthodox Jewish rabbi, known as the Lubavitcher Rebbe, compared the eclipse to a rainbow – also a natural phenomenon – but still served a divine message.

This idea echoes with the original Gemarah in Succa, which states that when we perform God’s will, we do not have to be afraid of the bad omens. However, it doesn’t resolve the fact that an eclipse is a predictable event, unlike the rainbow. Why does such a predictable and natural phenomenon serve as God’s will?

The answer is found in the question – it is precisely because an eclipse, being natural and predictable, serves as a warning from God. Human beings are a “fusion” of the physical and spiritual. We have a physical, temporal body and an eternal, spiritual soul. God’s commandments (mitzvot) allow us to connect with the spiritual and invest in the eternal aspects of ourselves. Our desire to seek physical and bodily pleasures is what drives us to sin.

It is natural for us to seek and derive instant gratification from such indulgence and desire – otherwise, it would be considered bizarre if we resist those desires. They are part of us being human. However, God’s divine will should refine and direct our physical desires into holier pursuits. God’s will helps us make a better version of ourselves and rise above the physical world of instant gratification. If we succeed, God will provide for us by breaking the laws of nature and performing the most wonderful and extraordinary miracles.

That is why lunar eclipses or “blood moons” exist – they serve as a warning, for the very fact that they are predictable and a part of the natural order of the cosmos. But we do not have to depend our choices on the laws of nature. We can align them with God’s will and rise above the physical and natural order of things, transforming ourselves into simply super-natural beings.