Although traditional societies often have a deep understanding of ecological relationships, traditional or religious values might be in conflict with current environmental values. According to Islamic Law, some compost sources used for agricultural purposes are impure, especially human and pig excreta. This study examined how Muslim farmers perceive the issue of impurity of compost sources and the extent to which the conflict between traditional and modern values affects compost use. Questionnaires were distributed to 77 Muslim and 11 Christian farmers in Israel, examining their personal characteristics, attitudes toward compost use, awareness of its sources and advantages, and the influence of traditional perceptions on the tendency to use compost. Interviews were conducted with agricultural consultants and Muslim clergy. Although the use of compost was limited, a higher level of awareness was found among the younger and/or more educated Muslim farmers. Varied attitudes were expressed regarding the degree of purity/impurity; 52 % of the respondents expressed willingness to use compost if derived from pure materials. The agricultural consultants were acquainted with Muslim farmers who recoiled from the use of compost. The Muslim religious leaders stated that impure substances can be purified through biochemical reactions during the composting process and noted that the use of compost is preferable if chemical fertilizers are harmful to the environment. Although Muslim farmers expressed willingness to use compost if it was proved to be pure according to Islam, this paper addresses how, in practical terms, universal environmental policies may give rise to value conflicts in traditional communities.