Ebenezer

Then Samuel took a stone and set it up between Mizpah and Shen. He named it Ebenezer, saying, "Thus far has the LORD helped us." 1 Samuel 7:12
Some times we need reminders of what God has done. Samuel knew this when he set up a rock and named it Ebenezer. God gave Noah the sign of the rainbow. Joshua set up memorials on the banks of the Jordan River.
Peter says, "Dear friends, this is now my second letter to you. I have written both of them as reminders to stimulate you to wholesome thinking." 2 Peter 3:1
We need to have reminders to stimulate us to wholesome thinking.