Shaikh Wasiullah Allahabadi (Allah have mercy on him) wrote to a disciple ,

‘You are coming (to me) for so many days now, however, neither have you become involved in (religious) work as required nor have you developed the understanding as per my standards. The reason for this is not reading the essential books of Maulana (Ashraf Ali) Thanvi (Allah have mercy on him). Why is this so? This coming (to me) is just in vain or for religious betterment (Islah). 

The (religious/Islah) work starts after acquiring knowledge. What will an individual without knowledge do?

If you have understood something from this write it (back) to me’

Maktubaat e Islahi , wasiyet al Irfan, May 1995, page 19-20