1 Samuel 6:5-9

So you shall make replicas of your tumors and of your mice that ravage the land, and give glory to the God of Israel; perhaps He will lighten His hand [of judgment] on you and your gods and your land. Why then do you harden your hearts [allowing pride to cause your downfall] just as the Egyptians and Pharaoh hardened their hearts? When He had severely dealt with them and mocked them, did they not allow the people [of Israel] to go, and they departed? Now then, make a new cart and prepare two milk cows on which a yoke has never been placed; and hitch the cows to the cart and take their calves back home, away from them. Then take the ark of the LORD and put it on the cart; and put the articles of gold which you are returning to Him as a guilt offering in a box beside it. Then send it away [without a driver]. But watch, if it goes up by the way of its own territory to Beth-shemesh, then [you will know that] He has done us this great evil. But if not, then we will know that it was not His hand that struck us; this disaster happened to us by chance.”