A person once wrote a letter to Hazrat Shaikh Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) in which he asked the following question. He said, “Some of the people engaged in the effort of da’wat and tableegh told me that going out for forty days in the path of Allah Ta‘ala is important for me. However, in order for me to go in jamaat, I will need to take out a loan, and find someone to take my place and teach in the madrasah. I have found a substitute, but I do not have full confidence that he can teach the class correctly. Hence, what I need to know is that under these circumstances, is it correct and appropriate for me to go in jamaat or not? Please advise me, and I will do whatever Hazrat advises.”
In reply, Hazrat Shaikh Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) wrote the following. He said, “If the madrasah is pleased with the replacement and they feel that the teaching will not be affected by your absence, and you are able to acquire a loan, to go out for the forty days, in such a manner that it will be easy for you to repay the money, then in this case, it will be good for you to go. In fact, it will be very important for you to go out in the path of Allah Ta‘ala.
However, if these two conditions are not found, then definitely, you should not go.
(Qutbul Aqtaab Hazrat Shaikhul Hadith Moulana Muhammad Zakariyya (rahmatullahi ‘alaih) pg. 377)