Hazrat Shaikh Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) once mentioned the following:
There is an important aspect which I need to bring to people’s attention. The important aspect is that some people think that tasawwuf and tableegh are two separate efforts, and a person involved in one cannot be involved in the other. However, I openly state that this notion is not correct. The reason why this is not correct is that I am personally involved in both efforts; I am affiliated with the effort of tableegh and I am also affiliated with the effort of tasawwuf.
There are certain Mashaayikh who prevent their mureeds from participating in tableegh as they feel that (through associating with many people,) the mureed will not be able to be fully focused on his islaah. Nevertheless, it should be understood that these Mashaayikh preventing their mureeds is not a blanket ruling or a general principle that applies to all cases. Rather, various Mashaayikh have different approaches and they accordingly guide their mureeds based on what they feel is most appropriate for their specific condition and islaah.
In this regard, their prevention can be compared to that of a doctor who prevents the patient from consuming sugar due to his diabetes. Likewise, at times, certain patients are prevented from consuming salt, and certain patients are prevented from drinking water. If one has to view such patients and then think that these preventions apply to all people, then this will be incorrect.
For example, Hakeem Mas‘ood Ahmad (rahimahullah) had prevented my respected uncle, Moulana Muhammad Ilyaas (rahimahullah), from drinking water. Accordingly, Moulana Muhammad Ilyaas (rahimahullah) had abstained from drinking water for a period of seven consecutive years for health reasons. If any person now thinks that this is a general principle that applies to all people, then it will be incorrect.
Therefore, I am affiliated with my respected uncle, Moulana Muhammad Ilyaas (rahimahullah), and the effort of tableegh, and I am also affiliated with Hazrat Raipuri (rahimahullah) and the effort of tasawwuf. Hence, I wish to emphatically announce that as far as possible, people in tasawwuf should try to also participate in the effort of tableegh.
(Qutbul Aqtaab Hazrat Shaikhul Hadith Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) pg. 372-373)