This chapter deals with nature as a source of religious law in the Abrahamic religions from a historical and a systematic perspective. Traces of natural law thinking can be found in all Abrahamic religions, although Judaism, Christianity and Islam deal differently with the idea of humankind's perceiving the naturally just. A challenge is posed by the question whether the law of nature might be perceived without knowing of the revelation. Another challenge is the plurality that comes with natural law. In the Catholic Church, plural natural laws are avoided by centralism, by the magisterium’s generating a homogenous doctrine on natural law. The supernaturally grounded governance of the church gives to the church a “natural” order. Because of this, the legal order of the church may be regarded as the “natural law” of the church. Therefore, natural law in the church addresses two phenomena. In a narrow sense, it is applicable to norms perceived by human reason when studying natural things. In a broader sense, the legal order of the church itself is a “natural law”, as it legally frames the (super)natural order of the church.