Times when all positive appeals run off us like water off a ducks back. Times when we have no interest in a life line of hope. Come hell or high water we are intent on going our own way. When we walk a path that's independent of God, we get hurt and cause others harm that can linger for generations. Frequently the only way that God can get our attention to save us from self-destruction, is to hit us over the head with a ten foot 2x4.
Tough love becomes our life line of hope.
The snakes bit the Israelites and they began to drop like dead flies. That caused them to swallowed their pride and returned to the people whom they were ticked off with, Moses and God. Now God had their undivided attention and could offer them a positive life line of hope. Because God's purposes are for our salvation, God told Moses to mount a brass snake on a pole where all the people could see it. He told Moses that the life of any snake bite victim would be spared if the victim would turn and look at the brass serpent.