COMMENTARY on 12:98
Mustafa Khattab:

Translation:
He said, “I will pray to my Lord for your forgiveness.22 He ˹alone˺ is indeed the All-Forgiving, Most Merciful.”
Commentary:
22   Jacob (ﷺ) delayed the prayer for his children to be forgiven until pre-dawn, which is a blessed time for supplication.

 

A. Yusuf Ali:

Translation:
He said: "Soon 1776 will I ask my Lord for forgiveness for you: for he is indeed Oft-Forgiving, Most Merciful."
Commentary:

1776  He fully intended to do this, but the most injured party was Joseph, and it was only fair that Joseph should be consulted. In fact Joseph had already forgiven his brothers all their past, and his father could confidently look forward to Joseph joining in the wish of the whole family to turn to Allah through their aged father Jacob in his prophetic office .