There is a fading of glory that is occurring. Things that are not built on the rock are going to have problems when the flood comes. Old ways of success that involved cheating, unethical dealings, and fraud won't work any more for certain people. Alliances that believers have made that are ungodly will come to light; be exposed, cancelled; and rendered null and void. Those who continue in them will fade and become irrelevant to the kingdom of God, like the men who sewed up the curtains in the temple that were ripped when Christ rose from the grave.
Jacob's glory will dwindle, Jacob's glory will fade. I believe that the reason that the people in question are called Jacob, rather than Israel or Ephraim is that God is saying,
"you have gone back to your old self, before I changed you, and are building upon that old self, instead of the new person who encountered Me and began to learn My ways."Because God loves his people, he disciplines them. God corrects his people. God re-delivers his people who become captured by the enemy.
Rude awakening precedes great awakening. There's no time like the present to get right with God, to get go of the things and ways that are not godly; that don't have Him in it. Better to humble one's self than have to be humbled. Repentance today keeps the darkness away.