«فَقُلْتُ اسْتَغْفِرُوا رَبَّكُمْ إِنَّهُ كَانَ غَفَّارًا»
So I said: seek your Lord’s forgiveness; He is surely most forgiving.
Istaghfirū means to seek forgiveness, while ghaffārā expresses abundant forgiveness. Both derive from the root gh-f-r.
The verbal echo ties the command to seek forgiveness to the divine attribute that gives it hope and purpose.