"I firmly believe that it was a calling and that God wanted me to," Martin Salia said in an April 2014 interview about why he worked to treat Ebola patients at Kissy Hospital in Freetown, Sierra Leone. Salia died of the disease on Nov. 17. (United Methodist Communications via YouTube)

Martin Salia, the doctor who died of the Ebola virus on Monday while receiving treatment in Omaha, said in an interview before he went to Sierra Leone that “it wasn’t going to be rosy… but I firmly believe God wanted me to do it.”

“There was just something inside of me that the people of this part of Freetown needed help,” he said in an  interview with United Methodist Communications in April.  “I see it as God’s own desired framework for me. And I’m pretty sure, I’m confident that I just need to lean on him, trust him, for whatever comes in, because he sent me here. And that’s my passion.”

Salia was in “extremely critical condition” when he was evacuated from Freetown in a specially equipped air ambulance for treatment in the United States at the Nebraska Medical Center, which has a state-of-the-art isolation facility equipped for treating Ebola patients.

A native of Sierra Leone with ties to Maryland, where his wife and two children live, Salia had initially tested negative for the virus; but a subsequent test came back positive on Nov. 10. He died at about 4 a.m. local time Monday, according to the hospital.

The doctor has been described as soft-spoken and highly dedicated to the life of doctor, and especially to traveling back and forth to West Africa, where he felt he was most needed.

“And so by the time you finish your training, you are more or less like the pastor, you become a pastor,” he said. “Whenever we want to start surgery, we pray. I am just being used as an instrument or as a surgeon to carry out God’s own plan for that person’s life.”

His son, Maada, told NBC News last week that Salia knew the risk of working in West Africa. But he wanted to help.

“Even though he knows the sickness is already out, he decided to still go and help his people because he wanted to show that he loves his people,” the son said. “He’s really, really a hero to me.”

Salia’s wife, Isatu Salia, who lives in New Carrollton, Md., told news media that he never stayed in the U.S. long because he believed people in Africa need him.

Salia was the chief medical officer and surgeon at the Kissy United Methodist Hospital in the capital city of Freetown. He also worked at several other hospitals in Sierra Leone.

Salia said his philosophy was simple: “God will heal them. And money comes.

“I firmly believe God wanted me to do this job. It was a calling.”

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In a statement, Salia’s wife thanked the hospital’s staff for trying to save her husband’s life.

We’re very grateful for the efforts of the team led by Dr. Smith,” she said. “In the short time we spent here, it was apparent how caring and compassionate everyone was. We are so appreciative of the opportunity for my husband to be treated here and believe he was in the best place possible.”

She traveled to Nebraska over the weekend but was able to see her husband only through a video connection set up by the hospital, a Nebraska Medical Center spokesman said.

According to the United Methodist News Service, Isatu Salia said she paid for the $200,000 ticket to fly her husband from Sierra Leone to the United States for treatment. The United Methodist Great Plains Conference is reportedly raising money to help cover the cost of travel and medical expenses.

Salia becomes only the second person to die of Ebola in the United States. The first, Thomas Eric Duncan, died at a Dallas hospital after contracting the virus in Liberia. He then flew to the United States.

Five other patients who contracted the virus in West Africa but were treated in U.S. hospitals all survived the illness, as did two nurses who were stricken with Ebola while treating Duncan in Dallas.

During a news conference on Monday, University of Nebraska Medical Center Chancellor Jeffrey Gold said the death of surgeon Martin Salia, who was treated at that hospital for Ebola, serves as a reminder of how deadly the virus can be at its advanced stages. (University of Nebraska Medical Center)