Here is Illinois pediatrician Pradeep Reddy’s game plan for the solar eclipse, which he has been eagerly awaiting: Watch awe-inspiring scientific spectacle. Then go inside and jump in the shower with clothes on. (Or at least run them through the washing machine.)

Reddy’s Hindu faith tells him to purify the clothing in which he watched the supposedly inauspicious cosmic event. Hindus for generations have taken all sorts of precautions to ward off the bad luck that they believe an eclipse foretells.

During Monday’s first cross-America eclipse in 99 years, believers of all faiths will have their first chance in decades to put their particular religion’s eclipse traditions into practice.

Capital Weather Gang's Angela Fritz breaks down what will happen when a total solar eclipse crosses the U.S. on Aug. 21. (Claritza Jimenez, Daron Taylor, Angela Fritz/The Washington Post)

For Muslims, it’s an opportunity to revisit a section of their scriptures that describes an eclipse occurring on the same day that the prophet Muhammad’s young son died, Imam Asif Umar said. During that eclipse, Muhammad gathered the community to pray; ever since, Muslims around the world recite the same prayer whenever they find themselves in the path of an eclipse.

Umar, who leads the Islamic Foundation of Greater St. Louis, will take students at his mosque’s school to a Missouri park, where he’ll talk to them about the scientific phenomenon of the eclipse as well as its spiritual meaning. “The sun is so much larger than the moon. But the moon is so much closer to the Earth,” he will tell them, explaining how the eclipse can occur. “It kind of just shows how God created it that way — from the Islamic viewpoint, in addition to being one of nature’s most spectacular sights, it’s also a reminder of the power of God.”

Dozens of church groups across the country have organized eclipse-viewing parties and trips. Most have the goal of preaching about God’s creation, but for the most part, Christianity also doesn’t assign specific prayers for an eclipse; Father James Martin, an author and expert on all manner of obscure saints, said he didn’t know a patron saint of eclipses.

Some interpret the eclipse as a sign of the coming end times, referring to biblical passages including Acts 2: “I will show wonders in the heavens above and signs on the earth below, blood and fire and billows of smoke. The sun will be turned to darkness and the moon to blood before the coming of the great and glorious day of the Lord.” A popular theory in certain evangelical circles posits that the Rapture will occur on Sept. 23, which is 33 days after this eclipse.

Jewish tradition offers specific blessings that believers should say upon seeing many natural phenomena — lightning, a mountain, a flower, a rainbow — but no blessing for an eclipse.

In fact, the Talmud — the rabbinical commentary on the Bible — describes an eclipse as “an ill omen for the world.”

“To what can we compare this?” the Talmudic rabbis wrote. “To a king of flesh and blood who prepared a feast for his servants and set a lantern to illuminate the hall. But then he became angry with them and said to his servant: ‘Take the lantern from before them and seat them in darkness.’”

Capital Weather Gang's Angela Fritz explains how math is used to determine the timing of a solar eclipse. (Claritza Jimenez, Daron Taylor, Angela Fritz/The Washington Post)

Nevertheless, some more liberal rabbis are encouraging their congregants to take Monday’s eclipse as an opportunity to give thanks to God for the wonders of the universe. Rabbi Daniel Zemel of Northwest Washington’s Temple Micah said it has been a years-long goal of his to see an eclipse; he sometimes reads an excerpt of a particularly poetic 1991 New York Times article about an eclipse in place of a prayer during Shabbat services.

Zemel will finally achieve his goal: he’ll watch this eclipse from Wyoming. He provided his congregation with suggested blessings including one from the traditional morning prayer service: “Blessed are You, Adonai, creator of the heavenly lights.”

The Hindu traditions are more specific. Reddy, who is a member of the board of the Hindu Temple and Cultural Society of Southern Illinois, said his community will go over the guidelines this weekend: Don’t eat any food cooked before the eclipse after it’s over. If you’ve stored any drinking water in your house before the eclipse, discard it. Try not to conceive a child around eclipse time, for fear of birth defects.

Hindu scripture teaches that an eclipse occurs when an angry spirit swallows the sun: “They have a score to settle with the sun and the moon. They basically swallow it. That’s what causes the light to go out,” Reddy said. “That is the old belief. Obviously the new belief is completely different.”

At Reddy’s temple, where many members like himself work in scientific fields, they’re balancing both old and new beliefs. They handed out eclipse glasses to the congregation last week, so members can safely enjoy watching the spectacle. And then those same members can go inside, jump in the shower in their clothing and go from room to room purifying their houses — though not necessarily with the traditional holy water from the Ganges. Reddy says at the temple, they’ll use a power cleaner.

It’s a balance of modern-day exuberance and traditional reverence that people of faith across the nation will enact on Monday.

Umar told members of his congregation that even if they can’t go to the mosque, they should pause from their workday to watch the sun vanish and say at least a sentence or two of prayer.

“Don’t do it with the intention, ‘I’m going out as a tourist,'” he said. “Do it with the intention of remembering God. Strengthen your faith by looking at it. Use it as a time to reflect on your purpose, why God put you in this world.”

If the moon rises in the east and sets in the west, why does the eclipse shadow travel from west to east? Dear Science is on the case. (Daron Taylor, Jorge Ribas/The Washington Post)

This story has been updated.

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