﴿وَلَكُمْ فِي الْقِصَاصِ حَيَاةٌ﴾
For you, in just retaliation, there is life. (Qurʾān 2:179)
The compact clause expresses extensive legal and social consequences: the institution of proportionate legal retaliation protects life. In ījāz al-qaṣr, the existing concise wording carries an unusually rich intended meaning; a missing word does not have to be reconstructed to make the expression intelligible.
In ījāz al-ḥadhf, by contrast, some verbal material is intentionally omitted and contextual evidence allows its recovery. The difference is measured by how the meaning is expressed, not by counting the number of words alone.