Henry was a key player last season as Barcelona won an historic treble of Primera Division, Copa del Rey and Champions League titles, scoring 26 goals in all competitions.But the France striker has netted just three times this season and has looked well below his best.
The former Arsenal star has found himself on the bench in most of Barca's recent matches and came in for further criticism in Catalonia this week after allegedly saying in an interview that he was "saving myself for the World Cup".
But Guardiola dismissed those quotes as inaccurate.
"I listened to the question and the answer in French, and it's not what he said," he said.
"No player is going to say 'I'm going to scratch my belly' in order to go to a World Cup."
"That's the price he has to pay for having won everything."
The Barca coach also dismissed talk of a supposed rift between the two.
"Why does there have to be a bad relationship? If he is not playing, perhaps it is because others are more in-form or inspired," he said.
Guardiola also challenged Henry to reproduce his brilliant form from last season.
"I want him to rebel and help us, because the 26 goals form part of the past - we need him to have that ambition that made him one of European football's greats in the last few years," he said.
"I want more from him and he knows that, but in the end it depends on him."
Guardiola is without centre-back Gerard Pique, who is suspended, and must decide between Gabi Milito, Rafa Marquez or Dmitro Chygrynskiy as his replacement.
Seydou Keita and Eric Abidal also miss out, but there is a place in the squad for youngster Jeffren Suarez.
Guardiola will come up against one of his good friends on Saturday.
The former Barca captain has long been an admirer and close friend of Almeria coach Juanma Lillo, and played under the Basque manager in Mexico, at Dorados de Sinaloa.
That was Guardiola's last professional club as a player and it ended in controversial relegation.
Lillo's record as a coach is chequered, but he and Guardiola share the same footballing philosophy.
That means Lillo is certain to opt for a more attacking formation than his predecessor Hugo Sanchez, who took an ultra-defensive Almeria side to the Nou Camp earlier this season.
Lillo has lost just one match since taking over from Sanchez late last year and Almeria are now nine points clear of the relegation zone following impressive victories over Atletico Madrid and Racing Santander in their last two matches.
And Lillo believes his side can compete against Barcelona.
"We're playing well and the feeling is good - we are obliged to compete," he said today.
Lillo believes Andres Iniesta is the best player in a star-studded Barcelona line-up.
"For me he is the best player in the world - the other players express themselves better when he is in the team," he said.
"Xavi is another who constantly improves the playing conditions for his team-mates, while (Lionel) Messi can tear you apart."
Corona is set to miss out again through injury, but Almeria should otherwise be at full-strength.
GUARDIOLA Wants HENRY T0 `REBEL`
