1 After this, the armies of the Moabites, Ammonites, and some of the Meunites declared war on Jehoshaphat. 2 Messengers came and told Jehoshaphat, “A vast army from Edom is marching against you from beyond the Dead Sea. They are already at Hazazon-tamar.” (This was another name for En-gedi.) 3 Jehoshaphat was terrified by this news and begged the Lord for guidance. He also ordered everyone in Judah to begin fasting.
As you can see there was a vast army approaching Israel and they were given very little warning. Typically they would send out messengers to the corners of the land to raise up an army to defend their country, but with the speed of this attack there was no time to do that. Jehoshaphat recognizes that their situation is desperate and he knows that the only way out is through prayer and fasting.
Sometime during their prayers he must have heard from God, because what he does the next day is VERY strange. Let's pick it up in verse 21:
21 After consulting the people, the king appointed singers to walk ahead
of the army, singing to the Lord and praising him for his holy
splendor. This is what they sang:
“Give thanks to the Lord;
his faithful love endures forever!”
And that's just how God works. In the darkest and most desperate times, He fights for us and provides victories in ways that we can never even imagine. What are you going through today? What are the giants facing you in this life? Through prayer and fasting, God wants to provide a way where there doesn't seem to be one.