The concept of “putting out a fleece” comes from the story of Gideon, a leader in Israel, in Judges 6. When God directed him to gather the Israelite troops to defeat the Midianite invaders, Gideon wanted to be sure it was really God’s voice he was hearing and that he understood His directions. He asked God for a sign to prove that this was truly His will. So he put out a piece of wool overnight and asked God to make it wet while keeping the surrounding dirt dry. God graciously did as Gideon asked, and in the morning the fleece was wet enough to produce a bowl of water when it was wrung out.

But Gideon’s faith was so weak that he asked God for another sign—this time to keep another fleece dry while making the surrounding dirt wet. Again, God complied, and Gideon was finally convinced that God meant what He said and that the nation of Israel would have the victory the angel of the Lord had promised in Judges 6:14-16. Putting out the fleeces was the second time Gideon had asked for a sign that God was really talking to him and would do what He said He would.

To put out a fleece means to ask God for a visible sign so as to verify or 'confirm' your prayer(s) is/are answered. E.g;

Samuel: Dear Lord, as I go to church this morning, reveal my spouse to me. Make her wear a red attire and cause her to sit beside me.
*Therefore any lady who sits close to him in church wearing a red attire is indeed confirmed to be his wife*

We put out fleeces in different ways, though. Christians, share you experience. Happy Sunday!