The Liga leaders were trailing 3-2 on aggregate and 1-0 on the night at Camp Nou before Messi's introduction from the bench after 65 minutes led to him claiming an assist for Pedro to take Tito Vilanova's side through to the semi-finals.
Messi was named as a substitute due to an injury he sustained in the first leg at Parc des Princes and Neville thinks that the player's impact puts the four-time Ballon d'Or winner beyond compare in world football.
"For me, greatness was redefined on Wednesday night. I would say a player who can change an entire stadium and turn a match around simply by walking on to a pitch redefines greatness," Neville wrote in his column in the Mail on Sunday.
"You put Messi into that team and you're transforming a very good team into the greatest team of all time.
"It was felt as though something spiritual had happened. You really had to be in that stadium on Wednesday night to appreciate the magnitude of Lionel Messi and the impact he can have."
Barca meet newly crowned Bundesliga champions Bayern Munich in the semis of the competition with the other tie pitting Real Madrid against Borussia Dortmund.