﴿ وَلِيَعْلَمَ ٱلَّذِينَ نَافَقُوا۟ ۚ وَقِيلَ لَهُمْ تَعَالَوْا۟ قَٰتِلُوا۟ فِى سَبِيلِ ٱللَّهِ أَوِ ٱدْفَعُوا۟ ۖ قَالُوا۟ لَوْ نَعْلَمُ قِتَالًۭا لَّٱتَّبَعْنَٰكُمْ ۗ هُمْ لِلْكُفْرِ يَوْمَئِذٍ أَقْرَبُ مِنْهُمْ لِلْإِيمَٰنِ ۚ يَقُولُونَ بِأَفْوَٰهِهِم مَّا لَيْسَ فِى قُلُوبِهِمْ ۗ وَٱللَّهُ أَعْلَمُ بِمَا يَكْتُمُونَ ﴾

“and mark out those who were tainted with hypocrisy and, when they were told, "Come, fight in God's cause" - or, "Defend yourselves" - answered, "If we but knew [that it would come to a] fight, we would indeed follow you." Unto apostasy were they nearer on that day than unto faith, uttering with their mouths something which was not in their hearts, the while God knew fully well what they were trying to conceal:”

And that He might also know the hypocrites, that is, so that the believers and the hypocrites might be distinguished at the level of differentiated knowledge.