The influence of Tertullian's account of the trinity has been variously assessed. It has been claimed that through Novatian, whose work (according to Jerome) was an epitome of Tertullian, and through Hosius, Tertullian triumphed at Nicaea and the homoousion went on. Indeed, in Tertullian ‘we first find the accurate definition and technical terms that passed over into Catholic theology, winning prompt acceptance in the West and securing when the time came – the grudging but certain approval of the East’. This is an impressive claim; but ideas rarely enjoy such unambiguous triumph.

Tertullian's achievement may even be embarrassing in a climate of anti-trinitarian debate. Through him and other theologians, it is wrongly claimed that Christians lost their belief in God as ‘one without further qualification’, for the understanding of trinity requires such ‘well informed and highly sophisticated powers of thought’ that many Christians are effectively tritheist rather than monotheist. Today, ‘the contrast between the apparent simple clarity of Jewish and Muslim monotheism and the apparent complexity of Christian monotheism remains a stumbling-block to Christianity's detriment’. Tertullian was aware of the difficulty here raised (Prax. 3.1); but he insisted that trinity was the way to one God.

TRINITY A NEW FAITH IN ONE GOD

Trinity is never a mere multiplication of heavenly beings; there must be one God. Trinity is the faith of the gospel.