﴿وَقُلْ جَاءَ الْحَقُّ وَزَهَقَ الْبَاطِلُ إِنَّ الْبَاطِلَ كَانَ زَهُوقًا﴾
Say: Truth has come and falsehood has vanished; indeed, falsehood is bound to vanish. (al-Isrāʾ 17:81)
The final clause «إِنَّ الْبَاطِلَ كَانَ زَهُوقًا» reinforces the preceding report through a more general and independent predication concerning falsehood. That is the force of tadhyīl: the second sentence embraces and strengthens the meaning of the first.
Tadhyīl is not necessarily verbal repetition; the new predication can also contribute a wider significance.