Jacob had twelve sons. Those twelve sons form the foundation of the nation of Israel. The nation of Israel represents the chosen people of God.
The family of Jacob is a reference to the nation, and the chosen people of God. In other words, those who have believed in the promised savior.
We know from prior studies that the genetic nation is not representative of Gods family, but the spiritual nation is Gods family, through their belief or faith in the savior.
So, Isaiah makes this appeal, to those among the nation that have not believed, to believe.
Isaiah makes an appeal to those who have believed, to walk, or live their lives, in accordance with Gods principles and mandates. To live their daily lives in accordance with doctrine, in other words.
Therefore, in application to us, this appeal is to all believers throughout history, to live their lives in accordance with Gods will.
God has placed each one of us in history at the proper time for us, such that our individual lives could be maximized within the spiritual life.
God had prepared for each one of us, a vast and blessed destiny, beyond our wildest dreams.
The nation of the Israelites were promised a kingdom of perfection, of prosperity, of the greatest period in all of history.
In the same fashion, all believers being the family of God, are promised the greatest destiny imaginable, and more, in heaven. But what is required is that we each live in accordance with Gods will. Which is simply living our daily lives in accordance with the principles taught by the Bible.
However, you cannot live by principles that you do not know. And you cannot know Gods will, unless you participate in a daily study of the scriptures.
God is going to be exalted. Doctrine is going to be exalted. The spiritual life of the mature believer is going to be exalted. But, if you are not a believer, if you are not spiritually mature or even moving in that direction, then you are not going to be exalted as much as is possible, if at all.
And that means that God will turn his back on you. Something that is going to be addressed in the next verse.
And that is not going to be good for anyone, and certainly not good for you.