Tafseer Ibn Kathir of AT TAUBAH [78]

أَلَمْ يَعْلَمُواْ أَنَّ اللّهَ يَعْلَمُ سِرَّهُمْ وَنَجْوَاهُمْ وَأَنَّ اللّهَ عَلاَّمُ الْغُيُوبِ

Did they not know that Allah knows their secrets and their private conversations and that Allah is the Knower of the unseen?