Does Judaism believe in aliens? What the Torah, Talmud and Kabbalah say

Neither the Hebrew Bible nor the Talmud discusses life on other planets directly. What Jewish tradition has is a handful of verses that later commentators read as hints of inhabited worlds, and a centuries-old debate over two separate questions.

Could life exist beyond Earth at all? Most sources leave room for it. Could there be other beings like humans, with free will and commandments? Most authorities doubt it. None of this is scientific evidence either way: as of late October 2026 no evidence of life beyond Earth has been found (are aliens real?).

The verse quoted most often comes from the Song of Deborah, after Israel's victory over Sisera: "Curse Meroz!" said the angel of the Lord. "Bitterly curse its inhabitants, because they came not to the Lord's aid" (Judges 5:23). Who or what was Meroz? The Talmud (Moed Katan 16a) records two views in a passage attributed to Ulla: "some say that he was a great man" who failed to join the battle, while "others say that the reference is to a star." The star reading leans on an earlier line of the same song: "The stars fought from heaven; in their courses they fought against Sisera."

Hence the famous inference: if Meroz is a star and the angel curses "its inhabitants," perhaps it has some. The Talmud itself never says so; the leap was made by later commentators, above all Sefer HaBrit.

Sefer HaBrit, by Rabbi Pinchas Eliyahu Horowitz, was first printed anonymously in Brünn (today's Brno) in 1797. This Hebrew encyclopedia of science and philosophy was reprinted many times and read from Europe to North Africa. In the first part, third essay, the author reads Meroz as evidence that the stars were made to be inhabited and do hold creatures.

He also draws a firm line. In his words, there is "no doubt" that none of these worlds holds humans "in our image and likeness, possessing free will," because where there is no free choice, Torah and divine service do not apply. He also rejects an argument he attributes to Rabbi Yosef Albo's Sefer HaIkarim (15th century): that such creatures would be pointless, since the world was made for humans. Later writers have noted that it is not clear Albo meant this.

The Talmud (Avodah Zarah 3b) describes what God does at night, and one answer is that he "rides on his light cherub and flies in eighteen thousand worlds." Rabbi Chasdai Crescas, the 14th-century Spanish philosopher, asked in Or Hashem (book 4, discussion 2) whether many worlds could exist and concluded that nothing in Jewish theology rules it out. According to Rabbi Aryeh Kaplan, Crescas cited the 18,000 worlds as a possible hint while allowing that they might be spiritual worlds.

The Zohar (Vayikra, III 9b–10a) speaks of "seven earths" whose inhabitants differ in appearance, and in the same passage cites Rav Hamnuna Saba's teaching that the inhabited world turns like a ball. Kaplan read this as support for life beyond Earth, and cited the Tikunei Zohar's teaching that every star is called a world and that each righteous person will one day rule a star of his own. Others read the passage as describing our own planet, and when Kabbalah speaks of "worlds" it usually means spiritual realms, not planets.

In a talk on the Sabbath of Parshat Devarim in the summer of 1969, around the first Moon landing, the Lubavitcher Rebbe, Rabbi Menachem Mendel Schneerson, discussed life on other planets (printed in Torat Menachem, vol. 57). According to published summaries, he cited Meroz as showing that the Torah allows for inhabitants of other stars, while holding that humans on Earth are the highest of all creations, which is why the Torah was given here.

A better-known story comes from Velvl Greene, a microbiologist recruited for NASA's search for life on Mars. As Greene told it, and as Chabad.org has published it, he asked the Rebbe whether to continue. The Rebbe told him to look for life on Mars and, if he did not find it there, to look elsewhere in the universe. In another telling, the Rebbe asked "Why put limits on G-d?" and said that whether there is life in outer space "is a question for the scientists; it is not an object of faith."

Another thread of the debate is what the universe is for. Maimonides, in the Guide for the Perplexed (III:13), rejected the idea that the whole universe exists for the sake of humans and argued that each being should be seen as intended for its own sake. On that view, life elsewhere needs no special purpose.

In 1965 Rabbi Norman Lamm, later president of Yeshiva University, published "The Religious Implications of Extraterrestrial Life" in the journal Tradition. He asked what such a discovery would mean for the idea that humans are created in the divine image, and argued that it would not contradict the principles of Judaism. Rabbis today remain divided, with some Israeli Torah sites saying most sages deny physical beings beyond our world.

The Book of Ezekiel opens with a storm wind from the north, fire, four living creatures and gleaming wheels built as if one wheel were inside another. From the late 1960s, ancient-astronaut writers claimed this described a spacecraft. Josef Blumrich, an engineer at NASA's Marshall Space Flight Center, published The Spaceships of Ezekiel in German in 1973 and in English in 1974; he said he had set out to disprove the idea and ended up convinced. The book is generally classed as pseudoscience.

The text itself labels what Ezekiel saw: it opens with "the heavens opened and I saw visions of God" and closes with "that was the appearance of the semblance of the Presence of God." In Jewish tradition the "Work of the Chariot" is the core of mystical teaching, so guarded that the Mishnah (Chagigah 2:1) restricts who may study it. It is a prophetic vision, not a sighting report.

The Nephilim (Genesis 6:4, Numbers 13:33) get the same treatment online. Rashi explains the "sons of God" as sons of princes and judges, and the name Nephilim as men who "fell and caused the downfall of the world." Nachmanides reads them as unusually tall, powerful men of humanity's first generations. Pirkei de-Rabbi Eliezer preserves a tradition of angels who fell from heaven. No classical commentator speaks of visitors from another planet; that reading was born in 20th-century ancient-astronaut books.

Microbes on Mars or an icy moon would threaten none of these sources; creatures without free will are what Sefer HaBrit expected. The hard question would come only with intelligent beings able to choose and to ask about their creator, for example through a confirmed signal.

Even then, history suggests traditions adapt. In theologian Ted Peters' survey, most believers, Jews among them, said such a discovery would not shake their own faith. The Catholic Church has been preparing the ground for years (what the Vatican has said about aliens), and our day-after guide covers what else would change.