The speaker, Gen. Henry Rangel, suggested during a newspaper interview last year that Venezuela's military would not accept an opposition victory in the country's 2012 presidential vote.
Opposition lawmaker Juan Carlos Caldera said Rangel "told the country that if Venezuelans were to decide to change the government in 2012" the military would not accept it.
Chavez promoted the general after the comment, saying Rangel had been unfairly criticized by the opposition.
Governing party lawmaker Aristobulo Isturiz chided the National Assembly's 67 opposition congressmen for boycotting the session, saying they "look down upon the armed forces."
Rangel was singled out in 2008 by the U.S. Treasury Department, which accused him and two other members of Chavez's inner circle of helping leftist Colombian rebels by supplying arms and aiding drug trafficking operations.
Chavez dismissed those accusations as politically motivated.