Babylonian Talmud, Kiddushin 40b
Rabbi Tarfon and the elders were once reclining in the upper story of Nithza's house, in Lydda, when this question was raised before them: Is study greater, or good deeds? Rabbi Tarfon answered, saying: Deeds are greater. Rabbi Akiba answered, saying: Study is greater, for it leads to doing. Then they all answered and said: Study is greater, for it leads to action.
Text from the Babylonian Talmud, Kiddushin 40b