Barak is called by Deborah and told he will win the battle. We can assume he's some kind of military leader within Israel, or at least an experienced, but for some reason is reluctant to go into battle. He will go only if Deborah accompanies him.
Barak is often criticized because of this: he wasn't a real man, he wasn't committed to following God, etc. But what if we viewed Barak with a little less criticism? If someone delivered a message from God for and to you, wouldn't you feel better if that messenger of God accompanied you? Barak may have viewed Deborah as a good luck charm of sorts--God would be with him because God was with Deborah.
It may also be that he was unfaithful. But I wonder if, when we view him as unfaithful, we're reading ourselves into his story?
The real problem for Barak is that, inadvertently or not, his actions demonstrate that he does not fully trust God as God. The word of God is delivered to him but he wants the broker of God's word, the middle-woman, to accompany him, wrongly believing that the fulfillment of God's word (prophecy) will be delivered through the presence of Deborah, not on the strength of God's word itself. As a result, God will still deliver his people but Barak will not get the glory from this military victory.
The narrative of Judges is clear that even though Barak advances, it is God who does the work of routing Sisera's army (4:15). As a result of God's work, all of Sisera's fighters were killed. But Sisera was able to escape, which leads to the revealing of the real deliverer--the non-Israelite, Jael.
Here's what we can learn from Barak: When we follow God, and specifically when we do what he calls us to do, he gives us all the resources we need to serve him. There's no magic charm, magic prayer, magic person, or even magic book that guarantees God's presence with us. His promise is all we need.
May we trust God more.