Jesus Christ Himself said, ” blessed are those who are pure in heart, for they shall see God. “Matthew 5:8. God cares about our inward parts. He desires truth in the inward parts and observes our hearts. Psalm 51:6 and 1 Samuel 16:7. Obedience must be honestly expressed freely from the heart out of love to Him, knowing who He is. Not a intellectual conversion where you just have a change of behaviour, but not a change of heart. Having only the appearance of godliness, but the obedience is not from a willing heart. The thoughts and desires are conversely against, and not for the will of God.
God wants a pure heart, this means conversion. Conversion means a change of heart. A change of heart is a pure heart of pure thoughts, desires and imagination. The gift of faith with the assurance of His love constantly purifies the heart, which is part of the process of sanctification. Without the sense of His love , knowing from the depths of our hearts according to His word, there will only be a form of godliness, a head knowledge of the truth, but no application of it. There is no such thing as a half hearted Christian. People who have had an intellectual experience without it touching the depths of the heart are dead inside, while they may look prosperous.
If we regard iniquity ( lawlessness or sin) in our hearts God will not hear us. Psalm 66:18. We must therefore completely let go, and let God. When we let go we allow God to apply the help that is needed. By faith in God according to His word alone, changes the heart. Faith is to wait, trusting in God to apply the help of that which we can not do for ourselves. It is not to try and change ourselves legalistically with forced obedience, which God does not accept from us. To force ourselves to conform to His law, statues and precepts. Nor to do good deeds or an intellectual theological perspective of His own word. For it is the power of God, and nothing else that changes the heart according to His word.