Hakim al Ummah Mawlana Ashraf Ali Thanawi (Allah have mercy on him) said,

‘I consider that in this era keeping company of the pious (ahl Allah) is an absolute essential (fardh e ‘ain).

Moreover, my fatwa is that in these times keeping the company of and having close contact with the pious and elite (friends of Allah) is absolutely essential.

This is because, there can not be any doubts about taking the means of safeguarding one’s faith being essential.

And it has been established by experience that in these times safeguarding one’s faith (eman) is only possible by keeping company of the pious.  No spell works, with the blessings of Allah, after this relationship.’

Fayuz ar Rahman, page 123