We introduce a theory in which gravity emerges as a thermodynamic phenomenon from a scalar field that sets the local rate of quantum evolution. Building on T. Jacobson’s derivation of Einstein’s equations from the Clausius relation and E. Verlinde’s entropic gravity, this framework extends these ideas into a unified framework of spacetime thermodynamics. From this foundation, the theory recovers General Relativity in strong fields, yields MOND-like galactic dynamics in the weak-field limit, on cosmological scales predicts evolving acceleration without a cosmological constant, suggests a quasi-de Sitter inflation without a inflaton field, and provides natural explanations for the Hubble tension and the vacuum energy problem. From first-principles, it derives the MOND and Hubble constants from quantum field theory, consistent with observations.