God will open the hearts of whomever He wants to guide to Islam, but He will tighten the chest of one whom He has led astray, as though he was climbing high up into the sky. Thus, God places wickedness on those who do not accept the faith.
Qur’an 6:125
One whose chest (heart and mind) is left open for Islam (submission to His will) shall receive light from God. Woe to those whose hearts have become like stone against the remembrance of God. They are clearly in error.
Qur’an 39:22
Ahmed Eltawil 