Neil, who was selected in the sixth round (No. 161) of the 1998 NHL Draft, had 250 points (112 goals, 138 assists) in 1,026 NHL games, all for the Senators.
"Playing your entire career with one team, you have a lot of great memories," Neil said during his speech, "but this one will be forever lasting."
Neil played with Ottawa from 2001-2017.
"Obviously, I wouldn't be who I am today if it wasn't for my mom and dad," Neil said, visibly emotional. "My mom is not here with us today, but I know she would be so proud. She pushed me to be the best that I could be."
The Flesherton, Ontario, native began and ended his speech with his signature raise-the-roof arm wave, and the crowd obliged each time.
"When I would get in a fight, which happened quite a bit," Neil said, "I would raise my hands up after the fight to get the crowd pumped up. But the real truth behind it was to let my mom know I was okay."
Tweet from @NHL: Tonight, the @Senators sent Chris Neil���s No. 25 to the rafters forever. In true Chris Neil fashion, he exited the ice via the penalty box. 😅 pic.twitter.com/ffYE84pyAm
Despite having 2,522 penalty minutes (20th all-time), Neil was never suspended.
"That tells you that he never crossed the line," Senators general manager Pierre Dorion said. "Came close, but never crossed it."
Dorion reminisced about the importance of Neil's presence in Game 5 of the 2017 Eastern Conference Second Round, arguably the most memorable moment of his career.
"If I can tell one story about him," Dorion said, "we don't beat the New York Rangers the last time we made the playoffs if Chris Neil is not with us. He came in that series, changed the tone of the series, we beat the Rangers, and Chris had a lot to do with it."
The Senators didn't appreciate how New York Rangers forward Tanner Glass had treated Kyle Turris in Game 4, so Neil entered the lineup in Game 5. Glass took an interference penalty on Dion Phaneuf early in the second period, and Neil jumped in to send a message. It cost the Senators a power play, but there were zero complaints from Neil's teammates.
"That's the best penalty I've seen taken in a long time," said Turris postgame.
The Senators won Game 5 thanks to Turris' overtime goal, and went on to win the series.
"How many players played better because Chris played with them over that amount of time in a real tough era?" Ottawa coach D.J. Smith asked rhetorically Friday. "How many buildings did guys go into and get an extra foot or two feet because he was out there?"
You won't find many of Neil's teammates who disagree with that sentiment. Wade Redden, a Senators defenseman from 1996-2008, spoke with reporters Thursday.
"I look back to when he first came and joined our team and where we were as a team," Redden said. "Where we were lacking, he brought a lot of energy and a lot of toughness, obviously.
"He was obviously cut from a different cloth than the rest of us. He brought that to every practice. Every day, he kind of had that energy on and off the ice. And he never shied away from it. He was obviously fighting. He'd take on anyone that would come his way. And he was smart about it, and did it in a way that would benefit the team in the scope of a game."
Fittingly, Neil wrapped up the ceremony by exiting the ice the way he had done hundreds of times before, raising his arms in the air to pump up the crowd and entering the penalty box.
Neil's jersey hangs alongside Daniel Alfredsson's No. 11, Chris Phillips' No. 4 and Frank Finnigan's No. 8.
