[smazibummigue]

Aslamo Alikum,

Dear All,

How do we know if we have lock on our hearts or not?

If we do not ponder on Quran, then it means we have lock on our hearts.

Do they not ponder over the Qur'an, or are there locks upon [their] hearts?

بھلا یہ لوگ قرآن میں غور نہیں کرتے یا (ان کے) دلوں پرتالے لگے ہوے ہیں

Quran 47:24

Conclusion:
If you want to save your heart from being locked then you must ponder on Quran.

If we will not ponder over Quran, then God will lock our hearts.