Returning a supplication of forgiveness

[‘AAabdullah Ibn Sarjis  said: ‘I went to see the Prophet (saws) and ate from his food and then said to him:

غَفَـرَ اللهُ لَكَ يا رَسـولَ الله.

Ghafaral-lahu laka ya rasoolal-lah.

‘May Allah forgive you, O Messenger of Allah.’

he replied:

وَلَكَ.

wa-lak

‘and you.’]