In the end, his tears told the story.
"I know I can play but I don't think I want to," Favre said, choking with emotion in a news conference at Lambeau Field two days after he announced his retirement. "It's been a great career for me, but it's over."
Wearing an untucked collared shirt, blue jeans and several days' worth of stubble, Favre said he was convinced he could still play on Sundays, but had lost his passion to practice and prepare the way he would need to lead the Packers to another Super Bowl.
Given that fact, he could draw only one conclusion: It was over.
"As they say, all good things must come to an end," Favre said. "I look forward to whatever the future may hold for me."
After a farewell news conference that lasted just over an hour, Favre put his arm around his tearful wife, Deanna, and left the stage -- presumably for good.
He takes with him a Super Bowl victory, virtually every quarterback record worth having and the widespread admiration of his peers and fans.
The 38-year-old Favre also leaves with graying hair and a deliberate gait -- signs that the years were quietly taking a toll on the man who was celebrated for playing a serious and precise game with the carefree joy of a little boy.
He cried Thursday as he discussed his decision.
"I promised I wouldn't get emotional," he said. But as the tears flowed, he added, "I've watched hundreds of players retire and you wonder what that would be like. You think you're prepared ..."
Favre thanked the Green Bay Packers for letting him play.
"I hope that with every penny they've spent on me, they know it was money well spent," he said. "It wasn't about the money or fame or records. I hear people talk about your accomplishments and things. It was never my accomplishments, it was our accomplishments."
Favre is the NFL's only three-time MVP, and leads the league with 442 touchdown passes, 61,655 yards passing and 160 career victories. He started 253 consecutive regular-season games, more than any other quarterback in history.
Favre also holds the more dubious mark of 288 interceptions -- an indication of the wild streak that only made him more human to the fans who adored him.
The same was true of Favre's highly publicized struggles with an addiction to prescription painkillers, his support of his wife through a battle with breast cancer, and a memorable Monday night game against Oakland after he lost his father.
Favre's exit comes after a remarkable 2007 season, but his final pass was one to forget: An interception in overtime of the NFC championship game, a mistake that set up the New York Giants' field goal that sent the Packers home instead of to the Super Bowl.
Most folks figured Favre couldn't exit that way, especially when he had at least one more good year left in him.
But barring a change of heart in the upcoming weeks, months or years, the final chapter in his storied football career began Monday night.
Favre called Packers coach Mike McCarthy and told him he planned to retire, then finalized his decision in a conversation with Packers general manager Ted Thompson on Tuesday morning.
But until the news conference, Favre hadn't explained his decision to his fans. He said Thursday there was nothing left to prove.
"I'm going out on top," he said. "Believe me, I could care less what other people think. It's what I think, and I'm going out on top."
Favre's retirement came as a surprise to Packers executives, coaches and teammates, virtually all of whom expected him to return. And it was a shock to fans who sat patiently, year after year, while Favre flirted openly with retirement -- because, of course, he never really meant it.
To a generation of fans who watched Favre start every game since taking over as the Packers' starting quarterback during the 1992 season, it didn't make sense. He wouldn't just decide he was too tired to play and walk away.
Recent comments by Favre's agent, Bus Cook, stirred suspicions about the "real" reason Favre was retiring.
Had the Packers' front office not done enough to talk him into coming back?
Was Favre's retirement a knee-jerk reaction to the fact that wide receiver Randy Moss, a player Favre lobbied the Packers to sign a year ago, had re-signed with the New England Patriots without an apparent effort from the Packers?
Favre's comments Thursday indicated the decision was much simpler.
"I did it, but it got hard," he said. "I don't think it would get easier next year or the following year. It hasn't up until this point. It's only gotten tougher and something told me 'You know it's gotten too hard for you.' I could probably come back and do it. Suck it up. But what kind of a toll would that take on me, my family or my teammates? At some point it would affect one of those if not all of them. Maybe it has already. I don't know."
Some who know Favre have doubts that he will be able to spend Sundays on the couch when he still has the ability to play.
A bearded Favre said Thursday he had no definite plans for the future and did not know whether he would be involved in football or with the Packers.
"I don't even want to think about next year," he said. "Will I watch games? I'm sure I will. Will I be involved? I always made the joke I'd be here for an honorary coin toss. Well, that time may come, so I may be back for something like that. But as far as giving advice, I don't think that will happen."