A question to consider is, is it the nature of God that changes or just our view of God that changes through different stories? As we here stories of God and the miracles he creates our opinion of him and how we perceive god can change. If we agree with the actions God chooses to take we will see him in a ‘good light’, but if we disagree then our opinion will completely change. So I believe that it isn’t God that directly changes but the way people in the real world perceive him.
The miracles that God carries out are carried out through love and compassion for his people. It is God’s goodness that causes him to help people whether it is to relieve pain or suffering, through miracles. He helps people who deserve to be helped, and who have been true to God and his teachings, I don’t think that this suggests that he is ‘unpredictable’, as he is carrying out these miracles when he sees fit, and just because he doesn’t go around casting miracles to people, it doesn’t mean that when he does he’s being ‘unpredictable’, he’s just helping people when they truly deserve it.
God is not unpredictable, but I believe he is changeable. He changes the way in which he carries out miracles, but not the reasons behind it. He may not grant the same miracle to everyone, but his reasoning for carrying out this miracle is still the same throughout, his love for his people. In the story of Sodom and Gomorrah God demonstrates power by destroying these cities in Genesis 19. This shows God to be changeable but not unpredictable, as he threatens to do so before he does it, so it wasn’t exactly a shock to people as he had warned them previously.
If God did not care about the people and their feelings he wouldn’t bother creating miracles in the first place as he would just let people continue to suffer, and not help them when they need it or deserve it. For example, the story of Elijah, where because a widow helps Elijah when he has no food he rewards her by making sure she never goes hungry. This shows God rewarding the old widow for her kindness to Elijah.
Is unpredictable the same as unchangeable? I don’t believe that these two words mean the same thing. If something is unpredictable it means that it is not expected and that it comes out of the blue. Unchangeable means that something can’t be changed, and that it is the same throughout. These two words clearly aren’t the same and they both describe God is different ways. God can be changeable in many ways but he is not unpredictable. I don’t believe that miracles suggest an unpredictable God but sometimes in some circumstances God can be seen as being ‘changeable’.