Are there any forms of employment that a Christian should avoid?

Yes. A Christian should avoid any employment where he may have to use force against another man (such as the army or the police). He should avoid any position in which he has to swear an oath of obedience: no Christian should swear loyalty to any other man, since his loyalty is to Christ.

The Christian should also avoid unchristian situations, for example working in a gambling establishment, or in an arms factory, or in a place where strong drink is sold, or in a shop that sells evil books.