Why is the concept of God changing not significant for Christians?

For Christians, the concept that God does not change is profoundly significant; it means that our salvation and His promises are secure. In Hebrews 13:8, the assertion that 'Jesus Christ is the same yesterday, today, and forever' reinforces this truth. It highlights that the salvation we receive is not based on our fluctuating faith but on God's consistent character and His covenant of grace. Thus, believers can rest assured that, despite our failures or sins, God’s purpose and mercy toward us remain unchanged, affirming the doctrine of eternal security.