When God says it shall be well with you, it means you won’t fail again. It means you won’t know sorrow again. It means those who have written you off will soon be surprised.
It means all those who are mocking you will soon come and bow down before you. It means it doesn’t matter how many forces are against you, you are going to reach the top.
It didn’t say, “say to everybody that all will be well…”, it said, “say ye to the righteous that it shall be well…”. Only the righteous.
Who is righteous? The righteous is not somebody who is doing good. The Bible says all your good deeds are like filthy rags before Him. The only one who is righteous as far as God is concerned is the one who has been washed in the blood of Jesus Christ.