"Therefore, the Lord says: 'I am planning disaster against this people, from which you cannot save yourselves. You will no longer walk proudly, for it will be a time of calamity.'" NIV translation
The people had elevated their plans to a place above the plan of God for their lives. The root cause of this is pride in thinking that our ways are better than the ways of God. This disobedience was only going to be allowed for a certain period of time before God brings judgment on them. The wealth that they had acquired would not protect them and they would be humbled. The same type of thing is happening in many areas of life today. Men have disregarded the prescribed ways of God and, in effect, have become their own god. This, too, will only be allowed for a certain period of time before judgment is dealt.