Our main critique is based on L. Boff's argument that the Holy Trinity should inspire and criticise human society. This research is a critique of this argument which is at the centre of Boff's Trinitarian Social Model. Can Boff's argument be considered as a mere hypothesis or rather a fundamental axiom, i.e. a verified and accepted argument? The original contribution of this work is not only in the critique of the Trinitarian Social Model (TSM) of Leonardo Boff, using the Small Christian Communities (SCCs) as a case study, but also in the proposition of the Social Trinitarian Model (STM) for Tanzanian society. This Social Trinitarian Model is based on SCCs in relationship to an inclusive Tanzanian spirit of unity and hope. It also includes the human values of 'syn-bios,' 'syn-pathos' and 'syn-hodos.' These human values are related to the Trinitarian life, koin¿nia and perich¿r¿sis. In fact, in the Social Trinitarian Model, SCCs are like a 'foretaste' (prolepsis) of the Kingdom of God. Though this Social Trinitarian Model is based on the SCCs of Tabora in Tanzania, it is not exclusively for Tanzanian society. It can inspire other African societies and other parts of the world.