Allah Ta’ala says, ?And help one another in virtue and piety and do not help one another in sin and oppression.? (Maaidah 5:2). Abdullah ibn Masóod (Radhiallaahu Ánhu) narrates that Rasulullah (Sallallaahu Álayhi Wasallam) advised, ?Do not take a commitment (profession, business, etc.) that will involve one in acquiring the world (over religious obligations). (Mishkãt pg.441; Qadeemi).
In view of the above, it is permissible, in fact ideal for a person to practice a profession without him compromising his religious obligations. However, in a conflict between his professional duties and religious obligations, preference should be given to religious obligations.
As an Actuarist, if one will be advising in un-Islamic activities, for example, interest-related transactions, insurances, etc. then it is not permissible.
If one will not be advising in un-Islamic activities or advising Muslim clients to assist them to come out from un-Islamic transactions, for example, interest, etc. then it will be permissible and in fact an act of virtue.
In short, to be an Actuarist is permissible and much depends on which avenue one practices upon.
and Allah Ta’ala Knows Best
Mufti Ebrahim Desai