Within this present paper we reviewed a series of particularities of the process of professionalization of charity and of formation of social work were reviewed, and also we highlighted the differences between the specificities of the social work carried out by secular organizations as compared to that carried out by organizations with a religious profile. A model of social Christianity was discussed, highlighting the Christian, historical foundations of social work. We started our analysis from the theory expressed regarding the post-secular society by Jurgen Habermas, in order to outline the model of social Christianity and the manner of its manifestation in faith-based social work organizations, so that in the end we were able to draw a series of theoretical conclusions regarding the types of faith-based organizations identified in the literature. The empirical research consists of a qualitative study, based on the application of semi-structured interviews, with 25 persons, priests, social workers and monks involved in the socialphilanthropic activity of the Orthodox Church. The interviews were conducted between October 2018 and January 2019 within the Diocese of Iasi and were analysed using Grounded Theory. After analysing the results, emerged a theoretical model regarding the specific activity of the Romanian Orthodox Church (ROC) as a faith-based organization providing social philanthropic services.