Damar Hamlin was making a routine tackle when he went into cardiac arrest during a game Jan. 2 on national TV.
He spent over a week in the hospital after emergency responders administered CPR on the field.
Hamlin made his comeback Saturday, playing in the Bills' preseason opener against the Indianapolis Colts in Buffalo.
The safety made three tackles, including a big stop on a fourth down, before being taken out of the game.
In April, the 25-year-old was cleared to resume football activities, and he was a full participant during the Bills' OTAs earlier this offseason.
Earlier this month marked the first time Hamlin, along with the rest of his teammates, wore pads in practice. It was Hamlin's first time wearing pads since that night in Cincinnati.
He admitted he was "a little scared" amid his "roller coaster of emotions."
"But, like I say, my strength is rooted in my faith, and my faith is stronger than any fear," Hamlin said. "That’s what I want to preach up here, and that’s the message I want to spread on to the world. As long as your faith is stronger than your fear, you can get through anything. So that’s what I’m living by right now."
For Hamlin, it's been a methodical process without looking too far ahead.
"Trying to look forward, it just creates a lot of anxiety, a lot of unnecessary feelings," he said. "If you stay in the moment, it allows you to process it when you’re there."
Hamlin revealed his doctors concluded his cardiac arrest was caused by commotio cordis when he tackled the Bengals' Tee Higgins. According to the American Heart Association, commotio cordis is caused by "an extremely rare consequence of blunt force trauma to the heart that happens at exactly the wrong time in the heart rhythm, causing the heart to stop beating effectively."
This season will be Hamlin's third in the NFL. He was a sixth-round pick out of Pittsburgh.