Many Spanish dictionaries have had racial and religious bias over the centuries; the DLE is no exception. Christianity and Catholicism were described in favourable terms; Judaism, Islam, and Protestantism unfavourably.
Spanish dictionaries have historically reflected societal prejudices against certain religions and ethnicities, with positive portrayals of Christianity and Catholicism and negative portrayals of Judaism, Islam, and Protestantism. The DLE is not immune to this historical trend.