"The harder you work every single day, the more guys respect and trust who you are," Kelce said after signing a 6-year, $41 million contract extension that, by yearly average makes him the third-highest-paid center in the NFL.
Not bad for an undersized guy who was the 191st player in the draft 3 years ago.
"Even though I'm getting more money now, it's probably not going to change up my approach too much," Kelce said. "I'm still going to be the same guy. Come here and work hard each and every day. Try to improve. And hopefully, that'll rub off on the other guys."
Kelce is the first player from the league's 2011 draft class to sign a second contract. He still had a year left on his rookie deal, but he is such a critical component in the Eagles' offense that locking him up for the next several years was one of the team's top offseason priorities.
A day after re-signing six-time Pro Bowl left tackle Jason Peters to a contract extension, they did the same with Kelce.
"The center is essentially the quarterback of your offensive line," general manager Howie Roseman said. "There's so much responsibility on his shoulders. The way we look at it, it doesn't get much more important than a guy who's handling the football every play.
"When you talk about all of the traits Jason has - his fit in this offense, his fit in this building - I come down [from my office] for breakfast every day and he's [already] here. He's working. And it's February.
"It's because he loves to be here. He loves the game of football. He has an incredible passion for this city, for this football team. And he's an explosive player."
The 2011 draft wasn't the Eagles' finest moment. Danny Watkins in the first round. Jaiquawn Jarrett in the second round. Curtis Marsh in the third. Three swings, three bad-awful misses.
The one saving grace of that draft has been Kelce. Everybody thought offensive-line coach Howard Mudd had lost his mind when he threw the 6-3, 285-pounder out there with the first-team offense in training camp.
But when Mudd looked at Kelce, he didn't see a guy in over his head. He saw another undersized center: Jeff Saturday, the smart, athletic six-time Pro Bowler he coached for 10 seasons in Indianapolis.
"We had him rated higher than the sixth round," Roseman said. But he got sick at the combine. He weighed even less than we anticipated him weighing.
"When we went back and looked at [centers] who were at that weight, they generally had not ever gone higher than the sixth round. But he was a sixth-round pick that we were really excited to get. And that was because he was a really explosive athlete."
Kelce, a walk-on linebacker who moved to the offensive line as a Cincinnati freshman, started 16 games as a rookie and played well. Missed 14 games in 2012 after tearing an ACL, but came back last season and played at a Pro Bowl-caliber level.
With the new deals for Peters and Kelce, the Eagles have all five of their offensive-line starters signed though the next three seasons.
As the guy in charge of quarterback Nick Foles' blind side, Peters is the most important person on the Eagles' offensive line. But Kelce is a close second.
"Center has become the second-most important position on the offensive line to left tackle," NFL Network analyst Mike Mayock said.
"If you talk to Peyton Manning or Tom Brady or any of the quarterbacks that are drop-back quarterbacks, they'll tell you that the thing that bothers them the most is immediate pressure up the middle. On top of that, the center is calling the protections and coordinating the line."
Kelce understands his importance to the offense.
"From an individual standpoint, I put a good product on the field in terms of playing," he said. "But the center position, in terms of controlling multiple positions, the only position on offense that is comparable to it is quarterback.
"The center is in charge of a lot. It's not just you. So I think the more continuity you can have at that position, the more helpful it is."
Kelce would like to spend the rest of his career as the Eagles' center. That's why he agreed to a deal that ties him contractually to the team through 2020.
That's a long time. While his deal averages out to $6.8 million a year, it includes only $13 million in guaranteed money, which isn't a lot for a guy who appears to be on the doorstep of becoming a perennial Pro Bowler.
But Kelce doesn't care.
"They told me what the numbers were and I said that sounds pretty good to me," he said. "I think the longer for me the better, because I really, truly don't want to play for any other organization. I'm happy with this city, this team, these coaches. I'm really excited to be here, and I have been from Day 1."
He could have signed a shorter deal that might have allowed him the opportunity to really hit it big in 4 or 5 years. But that wasn't really important to him.
Besides, both Kelce and his agent, Jason Bernstein, seem to have enough trust in Roseman and owner Jeff Lurie that if he outperforms his contract down the road, they'll make it right.
"I think I have at this point more than enough money to be comfortable," Kelce said. "I wear sweatpants and T-shirts every day. I don't wear jewelry or anything. I don't know if I need that much. But this is certainly enough to live comfortably. I'm just happy to be here. Happy to be here through the long haul."
He has more than enough to pay off the mortgage on his parents' home in Cleveland, which will be his first order of business with his new deal.
"Other than that, I don't really have a selfish purchase, as of yet," he said.
When he finally decides on one, I'm guessing it won't be a closetful of suits.
On Twitter: @Pdomo