After Ehud died the people fell back into sin, and they came under the hand of King Jabin who reigned in Hazor. Sisera was Jabin's commander, and he oppressed Israel for twenty years. The roads were not maintained, and village life deteriorated. People traveled by hidden paths to avoid the army. Their crops and herds were taken and the people lived in terror.
Deborah was a prophetess, and I assume that this gave her credibility in the eyes of the people. She held court between Bethel and Ramah under the Palm of Deborah. Deborah received a message from God. She sent for Barak and told him he was to take an army of ten thousand men from the tribes of Naphtali and Zebulun and go to Mount Tabor. She would lure Sisera to the Kishon River where God would give them victory.
Barak began to quake. "If you go with me I'll go. But if you don't go, I won't go." (This makes me wonder why Barak was necessary.) Deborah said, "Because of the way you are going about this, the honor will go to a woman, not to you. A woman will defeat Sisera."
Heber was a Kenite who lived and pastured flocks near Kedesh. He was married to Jael. He had "friendly relations" with Jabin and, I assume, Sisera. It appears Jael did not share his affiliation with them.
Sisera commanded nine hundred iron chariots and an experienced army. God commanded the skies. Deborah and Barak and ten thousand men of Israel assembled on Mount Tabor waiting for battle. The storm caused flooding and the iron chariots became bogged in the mud of the plain. The men of Israel poured down the mountain side and destroyed the army of Sisera.
Sisera abandoned his chariot and fled to the tent of Jael. She was home alone. It was a severe violation of custom for Sisera to enter her tent, but he did and she allowed it. She gave him milk to refresh him, actually cottage cheese "in a lordly bowl."(KJV) He lay down to rest, and she took a hammer and drove a stake through his temple nailing him to the ground.
Deborah and Barak arrived soon after this, and she presented the scene to them. In the celebration after the battle, Deborah praised Jael's deed and honored her. The Song of Deborah is, perhaps, the earliest example of Hebrew poetry dating to the 12th century b.c.e.
Just as a technical point, I would like to cast doubt on the pictorial representation of the act. I cannot see that Jael could take a hand tool and drive a peg through his skull. I think that would wake him. I believe she used something like a sledge hammer to drive a railroad spike. I envision an implement on the hammer that would affix the spike to the hammer until it was struck with one full blow. Since the women were responsible for setting up the tent, I am convinced that she was able to accomplish this. Just a thought--