Lennon is angry that Brown, a £4.4million buy from Hibernian in the summer of 2007, remains the subject of repeated criticism that Celtic overpaid for his services.
Speaking ahead of Sunday's first home Scottish Premier League game of the season against St Mirren, Lennon railed at Brown's detractors by insisting the midfielder had never let him down.
Brown did claim the SPFA Player of the Year prize in 2009 which seemed to silence his doubters, but his form was more uneven last term reopening the argument about how much he does for Celtic.
Lennon, though, promised he has never questioned his skipper's contribution since taking charge of the club following the departure of Tony Mowbray in March.
He said: "There's this apparent conundrum about Browny, but I don't see where all the criticism comes from at times.
"Since I've taken over he's been very consistent and again pre-season and coming into the season he's been very good.
"He's a very strong player for me and I thought as the Utrecht game went on he got better and better so I've no worries or qualms about his performances since I've taken over and I think there's more to come from him, as well."
Lennon says he now has the kind of dressing-room he has long craved at Parkhead, with Brown typical of the type of character he likes to see lining up on his side.
The Celtic manager has brought a number of players into the club during the summer from a whole host of locations, but the one thing they have had in common is the way they go about their football.
This Celtic team is starting to reflect Lennon's own image, but he conceded the real test is yet to come as first impressions can be misleading at this stage of the season.
Lennon added: "There's a good spirit among the players, we've got good personalities.
"I like their character and what they've brought to the club, but then I liked the nucleus of the squad we had last year as well so there's a good balance and blend there.
"It's very early for clear-cut opinions, until their backs are against the wall we won't know what character they will have, but the early signs have been promising."
Celtic's last meeting with St Mirren ended with a 4-0 defeat which ultimately spelled the end of Tony Mowbray's short tenure at Parkhead.
But Saints midfielder Hugh Murray expects that infamous clash to have no bearing on this weekend's game.
"It was nice to get a result last year but that's in the past," he said.
"It's a new St Mirren side and Celtic have brought new faces in as well so I don't think there will be a lot of players who played in that game.
"From our point of view, the new boys here are just looking forward to the game at Parkhead."
Lennon will, of course, be at the Celtic helm this time around, and Murray added: "I'm sure they will have a lot of fight in them.
"They won't accept losing cheaply and he will instil that in his team.
"It's not really for me to say if that fight was missing in the last game we played against them.
"But Neil Lennon, as a player, hated losing, and I'm sure he will spread that passion on to his team."