Saul, by his disobedience, led the people of Israel to come close to total destruction hundreds of years later.

1 Samuel 15:1. Samuel also said to Saul, the LORD* sent me to anoint you king over His people, over Israel. Now therefore listen to the voice of the words of the LORD*. 2. Thus says the LORD* of Hosts, I remember what Amalek did to Israel, how he laid wait for him on the road, when he came up from Egypt. 3. Now go and strike Amalek and utterly destroy all that they have, and do not spare them, but slay both man and woman, infant and suckling, ox and sheep, camel and donkey. 4. And Saul gathered the people together and counted them in Telaim, two hundred thousand foot soldiers, and ten thousand men of Judah. 5. And Saul came to a city of Amalek and laid wait in the valley. 6. And Saul said to the Kenites, Go! Leave! Go down from among the Amalekites! Lest I destroy you with them for you showed loving kindness to all the children of Israel, when they came up out of Egypt. So the Kenites departed from among the Amalekites. 7. And Saul struck the Amalekites from Havilah until you come to Shur, which is over against Egypt. 8. And he took Agag the king of the Amalekites alive, and utterly destroyed all the people with the edge of the sword. 9. But Saul and the people spared Agag, the best of the sheep, of the oxen, of the fatlings, the lambs, and all that was good and would not utterly destroy them, but everything that was vile and refuse, that they destroyed utterly.