This study aims to analyze the basis for the judge's consideration by using "other rules" (read: ijtihad) in adjudicating case No. 183/Rev.G/2021/PA. Mdo and 258/Rev.G/2021/PA. Mdo about child custody in the Manado Religious Court, so the decision made really puts forward a sense of justice. The basis for the judge's consideration using ijtihad needs to be studied and analyzed in depth because in many cases, judges in deciding child custody cases tend to follow the provisions of the applicable laws and regulations in Indonesia, which are influenced by many legal positivism that views the nature of the law as positive norms in the legal system, namely by using the Compilation of Islamic Law, namely for children who are mumayyiz granted the right to choose custody and those who have not been mumayyiz are handed over to the mother. This research is a qualitative research with a descriptive approach, and is analyzed using comparative juridical analysis. This study found that the judge's form of ijtihad was to have dared to use child protection laws in child custody cases as a legal consideration. The judge's decision under the child protection law succeeded in quelling religious conflicts between two foster parents of different religions in the struggle for custody. The conclusion of this study proves that the judge in the Manado Religious Court has not merely become the mouthpiece of the law, but has become the inventor of the law. This fact can be seen from the two cases tried, which although they are the same case, but received different decisions from the panel of judges.