In the middle of a worship song on Sunday, the morning after Cuba’s electrical grid collapsed for a second time in six days, the preacher at Renewal in Christ Church in Havana said he had a message to share that came to him in a dream. 

Sunlight splashed in through an open window to the right of the raised platform where he stood, as a battery-powered light affixed to the ceiling shone weakly over the pulpit. A row of desk fans, plugs dangling, lined the top of the concrete walls of the shadowed sanctuary. 

Almost every plastic and metal chair was filled at this small evangelical church, built from two housing units along a block of row housing in East Havana, which, like most of the city on this morning, had no power. 

"If you are thinking of giving up, don’t give up, keep going, keep going," said Pastor Daniel Cisnero, sweat on his brow, eyes closed, his voice a shout. 

"It’s not the time to give up, it’s the time to keep walking holding God’s hand."

Over and over again he said, "Don’t give up." 

The congregation crowded toward the front, arms raised. A man strummed an acoustic guitar as Daymer Alfonso Monterrey, 37, tapped out a steady rhythm on the cajon, a box-like drum.   

"We are living hard times, as you know, moments when our faith is [tested]. But faith in [God] is enough for us," said Monterrey, in an interview with CBC News after the service.

"Sometimes we don’t have anything in the refrigerators, we are living hard times with the blackouts ... God is above the difficult times. He is above sometimes not having a plate of food to eat," he said.

The Renewal in Christ Church provides its members with a meal on Sundays and runs a program to send food to the elderly during the week.  

"Our church not only does the spiritual work, but we also do social work in our community to help the needy," said Cisnero. "Jesus preached, but he also met the needs of the people." 

Cuba is facing an uncertain future as the U.S. administration of President Donald Trump seems intent on forcing the collapse of the island’s communist government with an oil blockade that’s magnified the country’s existing infrastructure and economic weaknesses. 

Cuba’s aging power infrastructure, which depends heavily on oil to generate electricity, is straining under the fuel shortage. The energy crunch has unleashed a cascade of crises engulfing its public services and driving food prices nearly out of reach for large portions of the population.

The country suffered a nationwide blackout last Monday that lasted a little more than 30 hours. Cuba’s Ministry of Energy and Mines announced a second blackout had hit the country at 6:45 p.m. ET on Saturday.

Cuban authorities said late Sunday that the electrical system in Havana, which is regularly rationed between neighbourhoods, had returned to normal operation. 

Cuba hit by another nationwide power outage

Work was also continuing to restore power in the rest of the country, authorities said.

The United Nations has warned that the oil blockade could plunge Cuba into a humanitarian crisis. But the U.S continues to hold a hard line on the blockade, recently warning off a Russian tanker headed to Cuba. 

Trump has also strong-armed longtime Cuba ally Mexico into stopping oil shipments to the island nation.

Mexico has since sent at least two shipments of aid to Cuba and its government quietly helped a group of activists who have rallied to Cuba’s cause by organizing a supply run to the country by sea and air. 

Mexican President Claudia Sheinbaum gave a personal donation to the Nuestra América flotilla, said Nicole León Avilés, one of the organizers from Spain, in an interview with CBC News.

Sheinbaum’s party, the National Regeneration Movement (Merena), also donated to the flotilla, along with government lawmakers, organizers said. 

No fuel, no tourists: Cuba reels under Trump's oil embargo

Avilés left Friday on a fishing boat re-christened "Granma" along with more than two dozen vessels from Puerto Abrigo in Mexico’s Yucat á n state.

The group claims it is carrying several tons of aid, including bicycles, personal hygiene products, diapers, powdered milk, non-perishable food and medicine.

They are expected to arrive in Havana on Monday. 

Granma is the name of the yacht that ferried Fidel Castro, Che Guevara and other revolutionaries from Mexico to Cuba in 1956 to begin the armed campaign to overthrow the regime of Fulgencio Bautista.  

Other members of the Nuestra América campaign from various parts of the world landed in Cuba late last week and held a concert Saturday during a local festival that featured Irish rap group Kneecap.

The band finished its performance a little over an hour before Cuba’s electrical grid failed early on Saturday evening, plunging the country into darkness. 

Hospitals under strain in Cuba amid U.S. oil blockade

Shortly after el apagón, as the outages are called here, Claudia Hernández, 16, braided the hair of her friend Adrian Duarte, 16, in the glow of cellphone flashlights held by two of their friends on the second floor of a low-rise apartment in Old Havana. 

Next door, Hernández’s mother, Lisandra Yanes Barrios, 37, placed a battery-powered lamp above the entrance to the kitchen, where a pot simmered on a gas stove.

"This is so common now that you are just resigned to it, you really have no other option," said Yanes Barrios.

She said that the family had 55 litres of water remaining in two tanks to ride out the latest blackout. When the power goes out, the water pumps shut down, cutting off running water.  

Hernández shrugged it all off. 

"We’re used to this," she said. 

The one thing that has changed for her, she said, is the importance of the external battery charger for her cellphone. 

"I used to use less, now it’s more important," said Hernández. 

Yanes Barrios said things would be bad in the country even without an oil blockade. 

"In my opinion, [the oil blockade] has nothing to do with it," she said. "We have been forced to adapt."

On the street outside her building, a little girl played hopscotch by flashlight.