Hazrat Moulana Muhammad Ilyaas (rahmatullahi ‘alaih) once mentioned the following:
There is a great need for people to firmly hold onto ‘ilm and zikr in their lives. However, it is important that one understands what ‘ilm and zikr refers to.
‘Ilm and zikr refers to one not being unmindful and negligent of fulfilling one’s Deeni obligations at any time. (In other words, one practises upon one’s ‘ilm (Deeni knowledge) and fulfils the commands of Allah Ta‘ala in regard to the dictates of the ‘ilm at all times. Practising on one’s Deeni ‘ilm and fulfilling one’s Deeni obligations correctly is regarded as zikr). If one has to remain engaged in fulfilling his Deeni obligations at all times, without being negligent, then this form of zikr will be regarded as the highest level of zikr.
Therefore, to remain engaged in supporting the effort of Deen and propagating it is also a high level of zikr – on condition that while carrying out this effort, one remains mindful of the other commands of Allah Ta‘ala and fulfils them, and one also refrains from all the prohibitions of sharee‘ah.
(Malfoozaat Hazrat Moulana Muhammad Ilyaas [rahmatullahi ‘alaih] pg. 120)