The issue of financing churches and religious associations in Poland is still topical and remains one of the main subjects of public debate. This is confirmed by the fact that in 2024 the Council of Ministers of the Republic of Poland started working on the system of financing the Church Fund, including the pension scheme for the clergy. At present, the state’s financial support is provided mainly in the form of subsidies from the Church Fund for the maintenance and repair of sacred and ecclesiastical buildings of historical value or for the charitable and welfare activities of ecclesiastical legal entities. In the context of the proposed changes to Polish law, it is worth referring to historical legal regulations, including those of canon law. From the point of view of the Polish State and the Catholic Church, the fundamental acts regulating the system of financing the Church in the Second Republic were the Code of Canon Law of 1917 and the concordat between the Holy See and the Republic of Poland of 1925. In the first codification of canon law in the history of the Church, the ecclesiastical legislator regulated the institution of the church founder (patron or protector of the church), including their rights and duties. The main aim of this article is to analyse the canonical regulations and the state’s implementation of these regulations in the light of the concordat. It also argues that the abolition of these legal provisions was justified and that historical regulations should not be taken into account when designing new systemic solutions for the financing of the Church and other religious associations.