Now there was a famine in the days of David for three years, year after year. And David sought the face of the Lord. And the Lord said, “There is bloodguilt on Saul and on his house, because he put the Gibeonites to death.” So the king called the Gibeonites and spoke to them. Now the Gibeonites were not of the people of Israel but of the remnant of the Amorites. Although the people of Israel had sworn to spare them, Saul had sought to strike them down in his zeal for the people of Israel and Judah. (2 Samuel 21:1-2 ESV)
The people of Israel had made a treaty with them way back during the time of Joshua, more than two centuries earlier. Even though the treaty was made by them through the deception of the the Gibeanites, it stood in the eyes of God. If God brings famine on all the land because a 200+ year old oath is broken, how serious do you think God considers oaths? It certainly shows how committed He is to the oaths or promises he makes to us. And it should convict us regarding the flippant way we take oaths today. I think of marriage oaths and church membership oaths and oaths of office.
What oaths have you made?