The research presents the effects of observing the purposes of Islamic law when working with evidence of legal rulings that the fundamentalists disagreed about the authenticity of some of them, because these purposes are representative of the philosophy of Islamic legislation, and its goals, and that its handling has become not limited to explaining them in partial rulings only, but an important requirement for all who go towards renewing mechanisms Ijtihad is one of the efforts of the nation, including the Zalami scholar who presented a vision consistent with reality and emanated from the purposes of Sharia by invoking it as a methodology for dealing with the legal texts; Criterion for weighting when different; In order to achieve bringing interests and ward off evil, its statement is improved because of its effect in explaining the sufficiency of the law and its validity for every time and place.