In وَاسْتَغْفِرْهُ, the initial hamzah is hamzat al-waṣl; it is not pronounced separately when linked after wāw.
The sākin rāʾ follows fāʾ with kasrah and no intervening emphatic exception, so it is light.
In «وَاسْتَغْفِرْهُ إِنَّهُ», the first pronominal hāʾ is preceded by sākin rāʾ: do not invent madd ṣilah kubrā there merely because a hamzah follows.
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Wastaghfirhu: hamzat waṣl and rāʾ
Al-Kāfirūn and An-Naṣr: Applied Madd, Idghām, Ghunnah and Waqf
In وَاسْتَغْفِرْهُ, the initial hamzah is hamzat al-waṣl; it is not pronounced separately when linked after wāw.
The sākin rāʾ follows fāʾ with kasrah and no intervening emphatic exception, so it is light.
In «وَاسْتَغْفِرْهُ إِنَّهُ», the first pronominal hāʾ is preceded by sākin rāʾ: do not invent madd ṣilah kubrā there merely because a hamzah follows.