Villa's 83rd-minute strike against the South Americans, his fifth of the tournament in South Africa, set up a repeat of the Euro 2008 final in Vienna when Spain beat Germany 1-0 with a goal from Fernando Torres.
"We have time now to put the work in to get to the final and Germany will not be pleased that they have to play Spain," Villa told reporters at Ellis Park.
"The match against Paraguay was our most difficult so far and we know that when our opponent sits back and defends it is tough for us but we came through and the important thing is that the team is still alive," he added.
Villa again came to Spain's rescue in a dramatic encounter in which both sides had a penalty saved, following up on a Pedro shot that came back off the upright and netting with a strike that hit one post and went in off the other.
"Things are going well and I hope they continue to do so," Villa said.
"The goals are important but if you win by a big margin and you score once or twice it doesn't have the same value."
Andres Iniesta, whose weaving run through the Paraguay defence helped set up Villa's goal, said his Man of the Match award would not have been possible without the collective effort of the team.
"David (Villa) would say the same if he were sitting here," the midfielder told a news conference.
"The strength of this team is that everyone plays as a unit, we all know our job and that helps achieve our success."
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