Qur'an 3:167

وَلِيَعْلَمَ ٱلَّذِينَ نَافَقُوا۟ ۚ وَقِيلَ لَهُمْ تَعَالَوْا۟ قَـٰتِلُوا۟ فِى سَبِيلِ ٱللَّهِ أَوِ ٱدْفَعُوا۟ ۖ قَالُوا۟ لَوْ نَعْلَمُ قِتَالًا لَّٱتَّبَعْنَـٰكُمْ ۗ هُمْ لِلْكُفْرِ يَوْمَئِذٍ أَقْرَبُ مِنْهُمْ لِلْإِيمَـٰنِ ۚ يَقُولُونَ بِأَفْوَٰهِهِم مَّا لَيْسَ فِى قُلُوبِهِمْ ۗ وَٱللَّهُ أَعْلَمُ بِمَا يَكْتُمُونَ

And that He might know the hypocrites, unto whom it was said: Come, fight in the way of Allah, or defend yourselves. They answered: If we knew aught of fighting we would follow you. On that day they were nearer disbelief than faith. They utter with their mouths a thing which is not in their hearts. Allah is Best Aware of what they hide.