Muhammad Arsyad Al-Banjari who lived from 1710 to 1812 in Borneo, Indonesia, applied a model of integrating uses of the Banjarese tradition into Islamic Jurisprudence based on a dialectical constitution of qiyās, the legal argumentation theory for parallel reasoning and analogy, he learned from the Shāfi‘ī-school of jurisprudence (uṣūl al-fiqh). Our paper focuses in the model of integration proposed and practiced by Al-Banjari, a rational debate grounded on a dynamic view on legal systems. We will illustrate the method with the (...) help of two different kinds of qiyās deployed by Al-Banjari in order to argue for the rejection of some traditional Banjarese offering-rituals for avoiding disease or calamities (manyanggar and mambuang pasilih), and for the acceptance of the use of consuming the traditional drink called lahang made of the juice of sugar-palm. As our dialogical reconstruction shows, the development of the debates, particularly the first one, is quite sophisticated, with a Banjarese opponent that does not surrender easily to the rejection of his use of those rituals. (shrink)