Then God saw their works, that they turned from their evil way; and God relented from the disaster that He had said He would bring upon them, and He did not do it. – Jonah 3:10
God can have a change of heart.
Just ask Jonah. He found out all too well how God could swiftly shift from fury and anger to mercy and forgiveness. He learned a real life lesson on how much God rewards repentance.
God had it in for Nineveh. He was set on destroying the city and its people, but he sent a man of God to deliver His Word and reached their hearts.
If God can have a change of heart for repentant people, can you?