”This I say therefore, and testify in the Lord, that ye henceforth walk not as other Gentiles walk, in the vanity of their mind, Having the understanding darkened, being alienated from the life of God through the ignorance that is in them, because of the blindness (hardness) of their heart:” Ephesians 4:17-18.
Apostle Paul takes us deeper as he pinpoints “futile mind”, the “darkened understanding”, and the willful “ignorance” and emphasised that it is all rooted in “the hardness of their heart.” being the deepest disease, infecting everything else. Of course, Someones mental suppression of liberating truth is rooted in such persons hardness of heart. Be aware that if such hard hearts will not submit to the supremacy of Christ, take it or leave it, the blind minds cannot see the supremacy of Christ.
If any man will do Gods will, he shall know of the doctrine, whether it be of God, or not. Thus, ability to soften the stony-heart is mostly developed gradualy yet fascinating to/featuring the Holy Spirit, just as building stony-heart is also gradual but more fascinating to/featuring the d’evil. For the transgression of a land many are the princes thereof: but by a man of understanding and knowledge the state thereof shall be prolonged. I know that Holy Spirit and His active influence is required and effective in the softening of even the hardest stony-heart (Proverb 21:1). Besides, God saved us, not because of works done by us in righteousness, but according to his own mercy, by the washing of regeneration and renewal of the Holy Spirit.
The reason I say the Holy Spirit is required is because the word “walk not” relayed “be not conformed to this world” while it advanced “renewal” in Romans 12:2 so profitable “for us to apply it in our lives so that we may prove what is that good, and acceptable, and perfect, will of God. I pray for you and myself: May God open the eye of our mind (s), Amen!