<p>Time dilation is an important issue in the field of physics. Introduced by the special relativity theory, it means that the time duration spent by an entity to reach a certain destination depends on the movement and speed of the entity. Time dilation has been widely addressed in other disciplines, including philosophy, psychology, and motivation. However, it has produced practical and theoretical controversies in the literature. The new version of relativity theory resolves these issues by extending time dilation to conceptual and mental factors and taking a process-based approach to the development of universe. The purpose of this paper is to discuss time dilation in different scientific arenas and explicate it in motivation from the perspective of motivational congruence theory (MCT). The theory provides a new explanation for the underlying mechanisms of time dilation as a mental phenomenon in motivation. According to MCT, a congruence between the context and extrinsic and intrinsic motivations escalates overall motivation. This, in turn, results in high levels of effort and engagement towards the task and leads to mental time dilation. That is, the individual becomes so engaged with the task that their subjective estimation of time duration becomes shorter, compared to an objective measurement of the elapsed time. The study provides hypotheses for further empirical research. MCT’s view to time dilation aligns with advances in the fields of physics and philosophy. It contributes to the literature by presenting a new explanation for mental time dilation and elaborating the motivational mechanisms that underlie this phenomenon.</p>