This paper explores the jurisprudential principle of “the prohibition of two conditions in one sale” as a foundational rule in Islamic commercial law, and examines its applicability in contemporary Islamic finance contracts, particularly in the context of the Sultanate of Oman. The study is based on the assumption that overlooking or neutralizing this principle in some forms of Islamic financing may lead to contractual imbalance, potential deception, or implicit coercion—issues that contradict the objectives of Sharia in ensuring fairness and mutual consent between contracting parties. The research adopts a descriptive-analytical methodology, with the integration of inductive and comparative approaches where necessary. It analyzes the classical juristic foundations of the rule, reviews practical contract models from the Omani market, and engages with previous relevant studies. The findings indicate that the principle is not merely a historical legal restriction, but a functional mechanism to prevent complex or unjust conditions that could disrupt contractual equity. The paper recommends explicitly incorporating this principle into Omani financial legislation, strengthening the supervisory role of Sharia boards in monitoring complex contractual stipulations, and enhancing the capacity of financial professionals through comprehensive training on the objectives of Islamic contract law.