A person need not explicitly deny something to be addressed with the emphatic wording normally used against denial. Their behaviour may suggest that they are acting as though the fact were untrue.
جَاءَ شَقِيقٌ عَارِضًا رُمْحَهُ، إِنَّ بَنِي عَمِّكَ فِيهِمْ رِمَاحُ
Shaqiq came displaying his spear; indeed, your cousins too possess spears.
Displaying the spear suggests exclusive strength. The particle “إِنَّ” answers that implicit suggestion. Rhetorical emphasis responds to conduct equivalent to denial, not necessarily an explicit denial.