He had doubts about his wife so he contacted her under a different name to test her
Question

                I work in one of the Gulf countries and my wife lives in one of the countries of East Asia. I had doubts about my wife and thought that she was having relationships with men in my absence. Hence I got in touch with her under a different name and she started talking to me believing that I was a different person. During these conversations I discussed very private matters with her and I even tried to make her commit some sins. In the end I found out from these conversations that she was innocent and fears Allah, which put my mind at rest as I wanted. 

I want to know:

1. Did I commit a sin by talking to her under a different name?

2. As I made her think that the person she was talking to was not her husband, did I encourage her thereby to commit the sin of talking about private matters?

3. As there was no other person in fact, will I be questioned about my pretending to be someone else? 

I hope that you can answer these questions, because I feel that I have sinned and I fear Allah in my heart.
Praise be to Allah.
      One should think positively of a Muslim and assume that he 
      is good and innocent so long as there is no reason for doubt and 
      suspicion, because Allah says (interpretation of the meaning):

    “O you who believe! Avoid much suspicion; indeed some 
    suspicions are sins. And spy not…”

    [al-Hujuraat 49:12]. 

    This Qur’aanic etiquette is one of the means of attaining 
    happiness and peace of mind, because thinking badly of people leads one to 
    seek out their faults and may lead to spying or doing something like what 
    you did, which was a mistake because it may make the wife dare to speak to 
    men about private matters, as you mentioned. 

    With regard to talking to her under a different name, it is 
    not a sin in and of itself. But we should speak about its motive and what 
    may result from it. If the motive was thinking negatively of her with no 
    evidence or grounds for doing so, then this is contrary to what Allah has 
    enjoined of avoiding suspicion. 

    Trying to make the wife commit some sins was also a mistake, 
    even if the intention was to test her. If we assume that she responded and 
    did fall into sin, that would not have proven that she had gone astray or 
    committed that sin before that, because a person may be weak at any moment 
    in the face of temptation. 

    Thus it is clear that this action was of no benefit; rather 
    it may be harmful and may encourage the wife to commit sin, and that would 
    increase your doubts without enabling you to find out the facts of the 
    matter. 

    It would be better to take care of your wife by getting in 
    touch with her and visiting her, and praying for good things for her, and 
    trying to increase her faith and piety, and letting her live near your 
    family or some righteous neighbours. These are means of attaining 
    righteousness and keeping away from evil. 

    Even more important than all of that is not being away from 
    her for a long time for the purpose of amassing money; rather you should 
    keep your journeys as short as possible, even if that results in more 
    expenses or reduces your earnings. Being keen to take care of your wife and 
    keep her chaste and give her her rights is more important and more 
    obligatory. 

    See also the answer to question no.
    13318 and
    145815. 

    And Allah knows best.