The king sent people to see what had happened to the animals of Israel, and they found that not one of them had died. But the king was still stubborn and did not let the people go.
They made their hearts as hard as rock and would not listen to the teachings of the Lord All-Powerful. And they would not hear the words he sent by his Spirit through the earlier prophets. So the Lord All-Powerful became very angry.
But Sihon king of Heshbon would not let us pass, because the Lord your God had made him stubborn. The Lord wanted you to defeat Sihon, and now this has happened.
So be careful and do not refuse to listen when God speaks. Others refused to listen to him when he warned them on earth, and they did not escape. So it will be worse for us if we refuse to listen to God who warns us from heaven.