"And Moses said, 'O my people, if you have believed in Allah'"—he already knew that they had believed and verified the truth, but this is a mode of speech among the Arabs; one says: 'If you are such-and-such, then do such-and-such,' while knowing full well that the person is indeed that way, yet intending that they act in accordance with what he has said to them.
﴿وَقَالَ مُوسَى يَا قَوْمِ إِنْ كُنْتُم آمنتم بِاللَّه﴾ وَقَدْ عَلِمَ أَنَّهُمْ قَدْ آمَنُوا وَصَدَّقُوا، وَلَكِنَّهُ كلامٌ مِنْ كَلامِ الْعَرَبِ؛ تَقُولُ: إِنْ كُنْتَ كَذَا فَاصْنَعْ كَذَا؛ وَهُوَ يَعْلَمُ أَنَّهُ كَذَلِكَ، وَلَكِنَّهُ يُرِيدُ أَنْ يَعْمَلَ بِمَا قَالَ لَهُ.
