Okay, so there was a man named Gideon who was chosen by God to lead the Israelites. Gideon was scared because the enemy army was much bigger than his own army, so he asked God for a sign that he would win the battle.
God told Gideon to bring his army to a river and choose only the soldiers who drank water by cupping their hands and lapping it up like a dog. Gideon did as God instructed and only 300 soldiers were chosen.
They all had horns and torches, and they surrounded the enemy camp at night. When Gideon gave the signal, they blew their horns and broke their jars to reveal the torches, making a lot of noise and light. The enemy army got scared and started attacking each other, so Gideon and his army won the battle without even having to fight.
So basically, Judges 7 is a story about a man named Gideon who had faith in God and won a big battle with only 300 soldiers.