Gideon demanded proof of God's promise that he would be the saviour of Israel, which was given (Judges 6, 36-40):
36: And Gideon said unto God, If thou wilt save Israel by mine hand, as thou hast said,
37: Behold, I will put a fleece of wool in the floor; and if the dew be on the fleece only, and it be dry upon all the earth beside, then shall I know that thou wilt save Israel by mine hand, as thou hast said.
38: And it was so: for he rose up early on the morrow, and thrust the fleece together, and wringed the dew out of the fleece, a bowl full of water.
39: And Gideon said unto God, Let not thine anger be hot against me, and I will speak but this once: let me prove, I pray thee, but this once with the fleece; let it now be dry only upon the fleece, and upon all the ground let there be dew.
40: And God did so that night: for it was dry upon the fleece only, and there was dew on all the ground.
