فَيَسْأَلَانِ الْعَبْدَ عَنْ رَبِّهِ وَعَنْ دِينِهِ وَعَنْ نَبِيِّهِ
They ask the servant about his Lord, his religion, and his Prophet.
The statement identifies three central subjects:
Lord — whom the person acknowledged as Lord and the one worthy of worship.
Religion — the religion the person followed.
Prophet — the person's position toward the Messenger whose mission reached them.
The issue is not merely a test of memorized phrases; it concerns the religious convictions to which the person actually assented and the position adopted during life.