13وَأَسِرّوا قَولَكُم أَوِ اجهَروا بِهِ ۖ إِنَّهُ عَليمٌ بِذاتِ الصُّدورِMuhammad AsadAND [know, O men, that] whether you keep your beliefs1 secret or state them openly, He has full knowledge indeed of all that is in [your] hearts.2While the primary significance of the noun qawl is "a saying" or "an utterance", it is often used tropically in the sense of "a statement"'. i.e., of a belief, an opinion, a teaching, a doctrine, etc. In the present context it evidently relates to man's beliefs in general, be they affirmative or negative: hence the plural form in my rendering of this term.I.e., He knows why one person believes in Him and another rejects this belief; hence, He takes man's innermost motivations, abilities and inabilities fully into account.