"I don't think she is qualified to be the chair of the DNC not only for these awful emails, which revealed the prejudice of the DNC, but also because we need a party that reaches out to working people and young people, and I don't think her leadership style is doing that," Sanders told CNN's Jake Tapper Sunday on "State of the Union," on the eve of the Democratic National Convention in Philadelphia.
As a result of the leaks, Wasserman Schultz has been removed as a speaker at the DNC this week, a decision reached by party officials Saturday, a top Democrat said. She is expected to gavel the convention in and out but that's it.
"She's been quarantined," another top Democrat said, following a meeting Saturday night.
Among the emails included in the release by hackers Friday were plots by DNC staffers to plant questions about Sanders' Jewish faith
ahead of the Kentucky and West Virginia primary contests.
"I am not an atheist," the Vermont senator said Sunday. "But aside from all of that, it is an outrage and sad that you would have people in important positions in the DNC trying to undermine my campaign. It goes without saying, the function of the DNC is to represent all of the candidates -- to be fair and even-minded."
He added: "But again, we discussed this many, many months ago, on this show, so what is revealed now is not a shock to me."
Still, Sanders made clear that he's not using the issue to re-open the Democratic primary after he's endorsed Clinton.
"The focus, though, that I am going to go forward on right now is to make sure that Donald Trump -- perhaps the worst Republican candidate in the history of this country; somebody that by temperament, somebody that by ideology, must not be president of the United States -- I am going to do everything I can to defeat him, to elect Hillary Clinton, and to keep focusing, keep focusing, on the real issues facing the American people," Sanders said.