Here's the No. 1 reason why Lurie - appropriately effusive in his praise - wouldn't declare Foles the Eagles' long-term quarterback of the future: He didn't have to.
Because Foles was chosen in the third round of the 2012 draft, the Eagles aren't financially strapped by a franchise quarterback-like contract, nor can they extend him to a franchise quarterback-like contract even if they wanted to.
Drafted players have to play under the terms of their rookie contracts through the third year, according to the NFL's collective bargaining agreement. So the Eagles have one more year to play with house money when it comes to Foles.
Which brings us to the obvious, No. 2 reason why Lurie avoided the question: The Eagles don't know yet if Foles is the quarterback who can lead them to a Super Bowl.
Foles will be the starter next season. He had a very good season and should - key word: should - improve with a full offseason as the No. 1 guy and another year with Chip Kelly.
But nothing is guaranteed. Some quarterbacks become exposed the more they play. Do the Eagles want to move forward beyond next season if Foles comes anywhere short of a title?
There are far too many variables involved to think that far ahead, but Lurie and Kelly don't want to get caught financially committing to a close-but-no-cigar quarterback (Tony Romo, for example). The current Foles contract allows them an Andy Dalton-like out after next season.
It's not a slap to Foles - or to his increasing legion of followers - to suggest that he may not be the answer to the question at the top. There was more evidence this season to say he will be, but there were some worrisome trends in three of the last four games.
In Saturday night's loss, Foles played well enough to have the Eagles up by a point with five minutes left in the game. He again didn't turn the ball over - a remarkable, season-long virtue - and made several strong throws and correct decisions.
But Foles has been holding the ball too long and taking unnecessary sacks and intentional-grounding penalties. The sack he took in the first quarter that backed the Eagles up 11 yards and initially took them out of field-goal range was egregious.
"I don't know what was going on in his mind," Kelly said. "I don't know where the coverage was and those things. But obviously we'd rather be back to the line of scrimmage if we can in those situations. He knows it."
Foles made similar mistakes against the Cowboys last week and two weeks earlier against the Vikings. In some cases, he made the smart choice and ate the ball, but those are choices he wouldn't have to make if he had the tools in the pocket to avoid pressure before it arrived.
There is the chance that Foles will develop those skills, but quick-twitch decision making is more nature than nurture. He has certainly had moments, but Foles missed receivers several times against the Cowboys and the Saints.
His two most important throws on Saturday were deep, up-for-grabs tosses on which he was bailed out. DeSean Jackson, whom Foles missed earlier, came back and outjumped a cornerback for a 40-yard catch in the third quarter and drew a 40-yard pass-interference penalty on an underthrown ball a quarter later.
"I'm going to make mistakes," Foles said. "I made mistakes tonight, but I'm going to keep playing and keep fighting."
The best quarterbacks find ways to win when they don't have their "A" games. Andrew Luck was brutal for more than a half in Saturday's other first-round playoff game, but the Colts quarterback led a dazzling rally past the Chiefs from a 28-point second-half deficit.
Foles was steady after a slow start, steady after the Saints jumped ahead, 20-7, in the third quarter. Aside from the October Cowboys game, he was steady - and sometimes spectacular - in his second season.
With Kelly's offensive mind, running back LeSean McCoy, and an improved defense, the Eagles can win with steady. But what if Kelly's play-calling is off or McCoy is shut down or the defense can't make stops. Is Foles the type of quarterback who can carry a team on his shoulders?
On Monday, Kelly will be asked if Foles is his starting quarterback moving forward. He will likely answer in the affirmative, but knowing him, he could find some way to deflect the question or sarcastically declare Foles his starter for the next 1,000 years.
Wait, Kelly already did that.
He knows it doesn't matter what he says. Foles still has to go out next season and prove he's the franchise's future.
BY THE NUMBERS
Nick Foles' passer rating, including the playoffs.
His record as a starter.
Yards per carry
2014 base salary