Seeking forgiveness for the deceased after burial

I want to know the authenticity of this Hadith:

“When Rasulullah (sallallahu ‘alayhi wa sallam) would finish the burial of the deceased, he would stay by the grave and say, ‘Seek forgiveness for your brother and beg steadfastness for him as he is now being questioned.’”

Answer

Imam Abu Dawud (rahimahullah) has recorded this Hadith on the authority of Sayyiduna ‘Uthman ibn ‘Affan (radiyallahu ‘anhu).

(Sunan Abi Dawud, Hadith: 3213)

‘Allamah Nawawi (rahimahullah) has declared the chain sound (hasan).

(Al Adhkar, Hadith: 480)

Also see here and here.

And Allah Ta’ala Knows best.

Answered by: Moulana Suhail Motala

Approved by: Moulana Muhammad Abasoomar