Praise be to Allaah.
We put this question to Shaykh Muhammad ibn Saalih
al-‘Uthaymeen, may Allaah preserve him, who answered as follows:
“Praise be to Allaah, the Lord of the Worlds. Military matters are
problematic, because they involve helping these kuffaar to wage war against the Muslims or
those who have entered into a treaty with the Muslims. If no such thing is involved, it
may be advantageous for Muslims to work in these armies so as to learn their secrets and
be aware of their potential evil. In other words, if working in these armies could be of
benefit, it may be permissible, otherwise it is not allowed.”
On this basis, if a person works as a preacher or daa’iyah or
imaam or muezzin, serving the Muslims and calling non-Muslims to Islam, then there is
nothing wrong with this.