Ferrer beat Harel Levy 6-1, 6-4, 6-3 on clay at the Torre Pacheco tennis club, and Ferrero defeated Dudi Sela 6-4, 6-2, 6-0.
Ferrer's accurate passing shots and consistent serve kept Levy off balance throughout the match, forcing the Israeli into making unforced errors.
Spain played without the injured Rafael Nadal and Fernando Verdasco, who wore their team colors and cheered from the sideline.
"Things are going well, and we achieved the objective of securing two points," Spain captain Albert Costa said.
Feliciano Lopez and Tommy Robredo will lead Spain against Jonathan Erlich and Andy Ram in Saturday's doubles in the best-of-five series.
Spain has never lost to Israel in three previous matches. The countries last met in 1996.
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