Mosiah 11:29

Now the eyes of the people were blinded; therefore they hardened their hearts against the words of Abinadi, and they sought from that time forward to take him. And king Noah hardened his heart against the word of the Lord, and he did not repent of his evil doings.

Wicked King Noah's hard heart was a conscious decision on his part. He was raised by a good father, and he knew right from wrong. Nevertheless, he chose to ignore God and please himself. God is merciful to those who try to do right but stumble. He does not brook direct insubordination, however. The condition of our heart is more critical than the condition of our bank account, our earthly titles, or even our good works.

Jacob 3:1

But behold, I, Jacob, would speak unto you that are pure in heart. Look unto God with firmness of mind, and pray unto him with exceeding faith, and he will console you in your afflictions, and he will plead your cause, and send down justice upon those who seek your destruction.

Even the pure in heart will have afflictions. If we lay those afflictions at the Lord's feet, however, he will help us bear the burden and comfort us.