Immutability is defined as something that cannot change. To be mutable means to be capable of change. Humans, for example, are mutable beings. In Christian theology, many use the word immutability to discuss the unchanging nature of God. This is specifically referenced to the biblical passage from Exodus 3:14, where God tells Moses, “I am what am,” sometimes written as “I am that I am.”
This passage has been interpreted as suggesting that God is a stable unchanging figure, representing immutability. According to some beliefs, it does not mean that God cannot appear in various incarnations, like Jesus, or the Holy Spirit, but these are unchanging qualities to God, and he is whatever he began as. Not all Christians believe in the immutability of God.
Some use the doctrine of immutability to suggest that bible based religion is the only way in which to access the kingdom of heaven. Changing times don’t translate to a changing God. He is and has always been what he is currently. They may look at the immutability of Christian law and suggest that even in the modern era, the only way to attain paradise is through following the same Christian laws.
Others may embrace the immutability of God but argue that biblical writings are reflective of the time in which they were written, and therefore may not always help guide the Christian, or the Jew to the right path in the modern world. They suggest that writings were always interpretive and represent the mutability of changing worlds, community and perspectives. In other words, even inspired biblical text may have been influenced by its writers.
Certain religious laws, like the ban on eating pork, are considered mutable because at the time of writing, the ban made sense. Pigs could easily transmit diseases to people. Now with safer dietary practices, eating pork is no more dangerous than consuming lamb or beef. Many Christians and some sects of Judaism make this argument.
Though immutability of God is key to many Christian religions, it is not always the spiritual doctrine of all Christian sects.