Hawzah News Agency – Imam al-Sadiq peace be upon him says:

إنّ لكَ قَلباً ومَسامِعَ، وإنَّ اللَّهَ إذا أرادَ أن يَهدِيَ عَبداً فَتَحَ مَسامِعَ قَلبِهِ، وإذا أرادَ بهِ غيرَ ذلكَ خَتَمَ مَسامِعَ قَلبِهِ فلا يَصلُحُ أبداً، وهُو قَولُ اللَّهِ تعالى‏ (أم عَلى‏ قُلُوبٍ أقْفالُها).

'You have a heart and ears to hear, and verily if Allah wants to guide a servant, He will open the ears of his hearts, and if He wills the opposite, He will seal the ears of his heart so it will never again be sound. This is the purport of Allah's verse: "or are there locks on the hearts?"

Source: al-Mahasin, v. 1, p. 318, no. 633