Temple Beth Yeshurun expected about 4,000 worshipers for Rosh Hashanah services Sunday at the synagogue along Beechnut.
Centerpoint arrived to fix the power, which did not come back on in time for services.
The power finally returned Monday morning just after 6 a.m.
Despite having no electricity, the services went on without a P.A system or working air conditioning, with people carefully making their way into the dark synagogue to pray.
"We had a very intimate service. Everybody in the dark, holding onto each other, praying and singing. It was a short service. It was incredibly meaningful," said Executive Director Andy Burger.
The temple was devastated by Hurricane Harvey. It spent $7 million to repair the damage.
It planned to unveil new seats as part of the repairs, but had to wait due to the power outage.
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