The first thing to say here is that when we employ someone to do any kind of work, we should do so on the basis of well defined criteria. The Qur’an mentions two of these which are most important, namely, ability and honesty. If you consider these, you are bound to find that they are essential in all types of work, whether at home, in an office, or in the marketplace. Moreover, neither of these is sufficient on its own. If a person is highly able and qualified to do a particular type of work, but is dishonest, the latter quality makes his ability of little use, because his dishonesty may undermine everything that he is able to do. On the other hand, if we are to choose an employee on the basis of his honesty only, he may not be able to do the work assigned to him.

Neither of these two qualities is exclusive to Muslims. There are people of both qualities, which follow all religions, or may be without religion at all. What we have to consider is whether the fact that the person’s beliefs will affect his work, or will produce any negative effect on the work to be undertaken or on those who come in contact with him. If not, then we can employ that person.

The Prophet, peace be upon him, employed a non-believer as a guide to show him an unfamiliar way to Madinah at the time when Quraish, his opponents, were trying to assassinate him. His guide was one of the best available to travel with him and his companion, Abu Bakr, across the desert following uncharted routes. Had his guide been dishonest, he could have informed Quraish of their route and the Prophet, peace be upon him, might have encountered great difficulties. The man’s honesty was of paramount importance.

I have written at length about life insurance and shown that it is permissible. Therefore, a person who works in life insurance is engaged in a legitimate job. As for people working in banking, they should look at the actual job they do. If it does not have anything to do with usury, then they may continue in their job since they are legitimate ones. On the other hand, if a Muslim works in a bank and his job requires him to be involved in transactions which are of usurious nature, then he should start looking for another job. He does not have to quit his job immediately. He is only required to make an earnest attempt which does not involve any breach of Islamic teachings. We must not forget that the Prophet has cursed the person who devours usury, the one who pays it and the one who writes the contract between the two and the witnesses to this contract.

What is intriguing in the way you have phrased your question is your usage of the expression "future wife," in reference to your woman correspondent, even before you are engaged. How can you justify such a description? Be that as it may, the answer to your question depends on your answer to a number of questions which you have to put to yourself. How serious are both of you about going ahead with the marriage? Do her parents know of your correspondence? And do you write with the thought that your letters may be read by them? If so, are they good Muslims who abide by the teachings of Islam? If you are writing to the lady whom you call your "future wife" in secret, and if both of you fear that your letters may fall into the hands of her parents because they will be very angry with both of you and probably take measures to stop this correspondence, then there is something essentially wrong with this relationship, and it is forbidden. In principle, there is no objection to a man getting to know his prospective wife's character and to find out whether her manners, education, temperament, characteristics and other qualities are to his liking. A man needs to be sure that his marriage stands a good chance of success. When writing, however, Islamic standards of morality must be observed. Their must not be love letters of the type poets and film-makers try to glorify. The purpose should be clear, and once the person concerned has determined that the other party will be a good marriage partner or the reverse, he should take practical steps accordingly, either severing the relationship or regulating it into an engagement and marriage.

As for seeing her, a Muslim woman has to observe the Islamic standards of propriety and decorum. A man who wants to marry a certain woman may see her in the presence of one or both of her parents, or her adult brother in order to determine whether to go ahead with his proposal and marriage. To see a woman in secret, without the knowledge of her family is not allowed.