Israel was a nation that was broken up into 12 tribes. Each of the tribes had their own territory assigned to them. I think we can consider this as similar to how the United States of America is broken up into states. Each state may have territory and boundaries, but it is all America. There were frequent raiders and incursions into these territories by enemy nations. This is one example. The area of Jabesh-Gilead would be in the territory of Manasseh. Nahash was counting on the rest of the tribes not caring about what happens here because "it is not our territory". He is counting on them believing it is not their problem, just the people of that region. One thing that I think has shown the Christian principles in our country is that people step up to help others in need not just in our local communities, but beyond. When flooding or hurricanes happen many people in areas not affected jump in to aid those in need. A lot of money is raised when these needs arise to help support those who have been affected. I think this is ingrained into our society from our founding on Christian principles. I hope this never changes honestly.
Saul was filled the Holy Spirit and became angry at what was happening. Anger is often seen as bad no matter what. Many people struggle with the idea that Jesus was mad in the Temple and chased out the money changers by flipping tables and carrying a whip. Anger is an emotion that often leads to trouble, but anger is not always bad. Righteous anger can often lead to change and action. Saul sent a warning to the rest of Israel to say we need to help at Jabesh-Gilead or else. There are things that should make us angry. The questions we need to ask are two-fold: What makes us angry? What do we do with that anger?