A study of the relationship between Plotinus and Christian philosophy is far less than an investigation of the overall influence of Platonism on Christianity. It treats of the effect on Christianity of a particular Platonist philosopher of the third century a.d.: A task at once more manageable in scope and more difficult to identify precisely. For Platonism had influenced Christian philosophers before Plotinus (particularly Justin Martyr, Clement of Alexandria, and Origen) and it was to be influential over hundreds of years on later Christians, many of whom knew Plotinus as just a prominent name in the tradition. However, to discuss the influence of Plotinus on Christianity is not only to discuss those who knew Plotinus at first hand, and liked (or reacted against) what he taught; it is also to consider the thought of those whose understanding of Platonism was affected indirectly by the particular brand of Platonism established as dominant by Plotinus and which in modern times we have learned to call Neoplatonism.