In the early thought of Arthur Prior, the idea of predestination played a considerable role. While on one hand he as a (largely) committed Presbyterian accepted the idea in some form or other, it also troubled him even from a very early stage of his intellectual life. From 1949 till 1953 a transition took place. During this time, he gave up his wider ambition of writing a History of Scottish Theology (and without doubt a highly systematical ‘history’ it would have been) and instead turned to modal and tense logic. At the same time he grew to be a firm defender of the notion of free will. There is no doubt that the connection between time, logic and determinism vs. indeterminism was a crucial theme and motivation from 1953 and onwards in the thought of Prior. This included some penetrating analyses of the notion of foreknowledge and its tense-logical implications. In this talk I will however focus on the theme of predestination in Prior’s early thought. It appears that his struggle with and finally rejection of predestination played a significant part in his development from being a practicing Presbyterian to his interest in tense-logic and indeterminism - and his ‘agnosticism’, respectively abandonment of religious beliefs.