" In the Old Testament, we read a lot about the staffs people carried around with them. They weren’t just walking sticks, or something to keep wild animals away. They were more significant than that.
Back in those days, people were nomadic. They were always on the move. They didn’t keep records with papers and computer files like we have today. Instead, they etched records of important events and dates on their walking staffs.
That was their way of keeping personal records. They’d etch notations such as, “On this date we defeated the Amalekites. On this date my son was born. On this date God brought us out of slavery. On this date God gave us water out of the rock.”
Their walking staffs provided a record of their history with God. When Moses parted the Red Sea, what did he do? He held up his staff. He was saying, “God, we thank You for all You’ve done in the past. We remember that You’ve delivered us time and time again.”
Moses was remembering the great things God had done. When David went out to face Goliath, he didn’t just take his slingshot. The scripture says he took his staff. On that staff, no doubt, he had etched, “On this date I killed a lion with my bare hands. On this date I killed a bear. On this date Samuel anointed me as king.”
David took his staff to remind him that God had helped him in the past. I can imagine just before he went out to fight, he ran over and read it one more time. That gave him the final boost. His attitude was, “God, You did it for me back then, so I know You can do it for me now. "

― Joel Osteen , You Can You Will: 8 Undeniable Qualities of a Winner