Onveranderlikheid (of immutabiliteit) is die eienskap van God dat Hy nie verander nie – nie in Sy wese, karakter, wil of doelstellings nie. In klassieke teologie beteken dit dat God volkome stabiel en betroubaar is, nie onderhewig aan tydelike prosesse of emosionele wisselinge nie. Waar mense verander in emosie, insig of gedrag, is God altyd dieselfde: gister, vandag en tot in ewigheid (Hebreers 13:8). Hierdie begrip gee gelowiges vertroue dat God se beloftes nie verander of verval nie.
Immutability is the attribute of God that He does not change – not in His being, character, will, or purposes. In classical theology this means that God is wholly stable and trustworthy, not subject to temporal processes or emotional fluctuations. Where human beings change in emotion, insight, or behaviour, God is always the same: yesterday, today, and for ever (Hebrews 13:8). This concept gives believers confidence that God’s promises do not change or expire.