Iniesta announced in April that he will leave Camp Nou at the end of the season following a glittering 22-year spell with the club.
Henry, who was on Barca's books between 2007 and 2010, was eager to praise the veteran midfielder for his contributions to the team, even if, to onlookers, he may not have been as much of a flair player as the likes of Lionel Messi and Ronaldinho.
"Andres is the guy who, first and foremost, does his talking with the ball," the Frenchman told Sky Sports News. "He's not very vocal off the field, you won't see a lot of interviews with him, but when he has the ball he can talk for days.
"I always think, when you look at him, if he walked past with a cap you wouldn't even know it was him. Chilling, low key, not doing anything - you throw him a ball and he turns into Superman. You can't grab him, he'll play one-twos to get past you, it's annoying. But it's all in his head. Look at him - did he have a little two-three step to get past you? Yeah. Was he quick? Not really. Was he strong? Not really.
"It's very difficult to keep it simple when you can do more, and Andres does whatever the game is asking him to do. He wasn't maybe the one scoring the goals or racking up assists, but when I say he was the guy before, people will ask me: 'What's that?' The guy that controls the tempo of the game.
"The one who makes your team tick, decides when we go or not. Then you have the likes of Neymar, Samuel Eto'o, Ronaldinho and obviously Lionel Messi who did what they did. But if you don't have that guy who controls the rhythm and the tempo of the game, makes things tick and decides when it's time to keep the ball, it's not the same. He was a joy to play with, what a player and what a brain."
Iniesta is currently fighting to be fit for what would be his last El Clasico against Real Madrid on Sunday.