"Matic knows very well what I think about him - the importance for me about this player, who is a really good player, a top player, very important for our team", he told Sky Sports.
Neville said it was "strange" for a manager to speak so favourably of a player that was sold to a direct rival.
Matic, 29, joined United for £40m ($52m) on a three-year deal in July, becoming the club's third summer signing after Victor Lindelof and Romelu Lukaku. "You saw that in the UEFA Super Cup game - he'll fit very well in there", Lampard said.
"You respect that if that is the case".
"He did that job for Chelsea with great tactical discipline".
This is Mourinho's second tattoo after he had'Tami inked on his wrist in reference to his family
"In our period of dominance he was what we want him to be: to move the ball in a simple way, to give balance to the team, to start building from the back".
Pogba scored just the nine times in all competitions last season, only five of which were in the league, as United limped to a sixth-place finish.
Chelsea are now preparing for their Premier League opener against Burnley at Stamford Bridge on Saturday as they look to get their title defence off to a winning start.
The midfielder rejoined Jose Mourinho for £40million, opting to leave last season's Premier League champions for Old Trafford. Although disappointed about losing Matic, Lampard appears very optimistic about the future of the new Chelsea man Bakayoko. Bakayoko has not and I saw him in the Champions League a year ago.
"And I'm hoping he'll do that with United - freedom for [Paul] Pogba, [Anthony] Martial, [Jesse] Lingard and [Henrikh] Mkhitaryan - these players really need to step up this year I think".