Former President Jimmy Carter spoke candidly about his recent cancer diagnosis in a press conference Thursday, revealing that the cancer that has spread to parts of his brain.

While speaking at a closed-door event at the Carter Center in Atlanta, Georgia, the former Democratic president stated that he plans to continue to fight against the disease, but that his fate is ultimately God's hands. He also announced that he was scheduled to receive his first radiation treatment later that afternoon.

The 39th president of the United States revealed last week that he was diagnosed with cancer, which began in his lungs and then spread throughout his body. On Thursday, he admitted that he initially thought he had only weeks to live when he first learned of the diagnosis.

"I just thought I had a few weeks left (to live), but I was surprisingly at ease -- much more so than my wife was," said Carter.

However, now he's more optimistic, even though examinations discovered "four spots of melanoma on my brain," he said.

The former president went on to say, "I have had a wonderful life. I'm ready for anything and I'm looking forward to new adventure," Carter said. "It is in the hands of God, whom I worship."

Carter also noted that his strength lies in his deep religious belief, and he pledged to continue teaching Sunday school at his church "as long as I'm physically able."

"I do have deep religious faith, which I'm very grateful for, and I was pleasantly surprised that I didn't go into an attitude of despair or anger or anything like that. I was just completely at ease."

After serving in the White House from 1977 to 1981, Carter and his wife, Rosalynn, opened the Carter Center in 1982, which works to combat poverty, hunger and global conflict. The noted humanitarian and former Georgia governor also received the Nobel Peace Prize in 2002.

Watch a clip of his press conference below.