The passenger who fell off a cruise ship last week said he spent 20 hours in the water before he was rescued by the Coast Guard.
James Grimes, 28, was pulled from the Gulf of Mexico last Thursday after falling off the Carnival ship Valor on the night before Thanksgiving.
In an interview with ABC News, the Alabama man said he "was dead set on making it out" of the ordeal alive.
"My worst fear is drowning," he told ABC News, "and that was something I did not want to have to face."
Grimes was on a cruise to Cozumel, Mexico, with 18 members of his family when he fell off the Valor last week, ABC News reported.
He admitted to having a few drinks prior to falling off the ship, but did not recall how many. Grimes was last seen at a restaurant where he told his sister he was going to the bathroom.
He said he does not remember excusing himself or his plunge into the Gulf of Mexico — only regaining consciousness in the water "with no boat in sight," he said.
"The Lord was with me when I was out there," he told ABC News, "because something was holding me up the whole time when I was passed out."
The next morning, Grimes' sister reported him missing after she learned he had not returned to his cabin.
While treading water for hours, Grimes fought rip currents and animals, including jellyfish and an unknown creature that bumped his leg but did not bite him, he said.
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Grimes told ABC News he was losing energy when a "stick came floating by."
"It looked like bamboo," he said, "so I started eating on it."
As nightfall came back around, Grimes said he became increasingly concerned but told himself to just keep swimming.
"I felt like I was given a chance right then ... you're alive for a reason ... that [fall] could've killed me," he said, "but I felt like from that moment on, I was trying to stay positive. And, you know when you're here, you're still alive for a reason."
After hours in the water, Grimes eventually spotted a tanker ship. He said he used his last bit of energy to swim to the vessel, which later contacted the Coast Guard for help.
Richard Hoefle, a Coast Guard Aviation Survival Technician for the New Orleans division, told local news stations that Grime "had about 30 seconds to a minute left" before he would have died in the water.
Grimes told ABC News he'd stripped off his clothes but waved his socks at rescuers when he saw them approaching.
Upon handing Grimes a rescue sling, Hoefle told CBS affiliate WWL-TV that the he "just collapsed into it."
Grimes was very "confused" and "disoriented" when rescuers reached him, he added.
Maintaining a positive mindset throughout the harrowing ordeal helped Grimes survive, he believes.
"I always thought there's a greater purpose for my life," he told ABC News. "Now, I know for sure I'm meant to do something on this Earth."
A GoFundMe has been started by Grimes' sister Sherry Boleen to help cover his medical bills.
Boleen says her brother "is currently without health insurance," and that any donations "will help" with the expenses.
"It's honestly and truly a complete miracle that he survived," Boleen wrote on GoFundMe.
She also thanked the Coast Guard, writing, "Without their help my brother would be lost."