(Proverbs 28:14 KJV) Happy is the man that feareth alway: but he that hardeneth his heart shall fall into mischief.
Hardening your heart happens as a result of our decisions and choices. We may not consciously say, “I am going to harden my heart”. But deciding to take the culturally popular position on an issue adds callus to our sensitivity to the leadership of the Holy Spirit. When we give into temptation once it usually becomes easier to push things a little further. When we are accepted by others because we did not stand up for uncomfortable truth it makes us want to be accepted even more.
So? Understand that each choice we make is a move toward either right or wrong. The concern is our long term direction. You do not achieve eternal life by traveling opposite of God.