That was Jay Fiedler's reaction to the Miami Dolphins bringing on Josh Rosen -- and Feidler would know, he's Jewish too!!!

In fact, Fiedler -- a 2002 inductee to the National Jewish Sports Hall of Fame -- was the last Miami Dolphins QB to lead the team to a playoff victory back in 2000.

So, with Rosen now in South Beach ... we hit up Fiedler to see if he had advice for his Hebrew brethren.

"The Jewish community down there will love him," Fiedler says ... "And, he'll probably get invited to quite a few Bar Mitzvahs along the way!!!"

In all seriousness, Fiedler thinks Rosen is a great addition to the Fins -- and says having a respected veteran like Ryan Fitzpatrick in the QB room will be HUGE for the young guy from UCLA.

Fiedler also dishes out some advice for Rosen ... and Josh should listen.

By the way, the Dolphins last playoff win was in 2000 ... when Fiedler led his squad over Peyton Manning's Indianapolis Colts in the wild card round!!!

Since then, the Dolphins were QB'd by guys like Daunte Culpepper, Trent Green, Chad Pennington, Chad Henne, Ryan Tannehill and Jay Cutler.

But, none of those guys were able to put a W on the books in playoff time.