God changed His mind and returned to His original plan—do you understand?
In Exodus 3, God had a plan for the children of Israel. When they messed up, He decided to destroy them, but Moses pleaded with Him, and God repented. This means God went back to His original plan of establishing them as a nation.
In the book of Samuel, God repented again concerning His covenant with the house of Eli. He chose Samuel and said that Eli’s descendants would die young so that Samuel would remain unchallenged.
So, the concept of God repenting means that God says something, changes His mind about it, and then returns to His original intention.