Judges 6:36-40 NIV
Gideon said to God, “If you will save Israel by my hand as you have promised— look, I will place a wool fleece on the threshing floor. If there is dew only on the fleece and all the ground is dry, then I will know that you will save Israel by my hand, as you said.” And that is what happened. Gideon rose early the next day; he squeezed the fleece and wrung out the dew—a bowlful of water.
Then Gideon said to God, “Do not be angry with me. Let me make just one more request. Allow me one more test with the fleece, but this time make the fleece dry and let the ground be covered with dew.” That night God did so. Only the fleece was dry; all the ground was covered with dew.
NIV: New International Version