From where did you come by this knowledge?

Reference: Siyar A’laam an-Nubalaa v14 p370

On the authority of Ibn Khuzaymah رحمه الله who was asked:

‘From where did you come by [this] knowledge?’

So he responded: ‘The Messenger of Allaah ﷺ said:

«The water of Zam-Zam is what it is drunk for.»

And certainly, when I drunk [it] I asked Allaah for beneficial knowledge.’