If my husband takes a second wife, will I be rewarded?
Question

                What is the reward, "ajr", for the first wife having patience ,"sabr", when her husband takes a second wife? Is there a special reward in this case, or is it the same reward for all women who obey their husbands and make their religious duties? If I would get to know about a special reward, things would be easier to accept. Someone said that the reward for this kind of woman was more than the reward for a mu´min leaving for jihad. And since Hajj is the jihad of a woman, accepting polygamy for the first wife is more than jihad. Is ther daleel for this, or do you know about another reward?.
Praise be to Allah.
    Firstly: 

    We do not know of any saheeh evidence which refers to the 
    reward mentioned, but al-Tabaraani narrated from Ibn Mas’ood that the 
    Prophet  (peace and blessings of Allaah be upon him) said: “Allaah has 
    decreed jealousy for women and jihad for men, so whoever bears that with 
    patience out of faith and in the hope of reward will have a reward like that 
    of a martyr.” This hadeeth was classed as da’eef (weak) by al-Albaani in 
    Da’eef al-Jaami’ al-Sagheer, no. 1626. 

    Secondly: 

    A woman’s being patient in obeying her husband is one of the 
    means of entering Paradise, as it says in the hadeeth narrated by Ibn 
    Hibbaan: “If a woman offers her five daily prayers and fasts her month 
    (i.e., Ramadaan) and guards her chastity and obeys her husband, it will be 
    said to her: ‘Enter Paradise from whichever of the gates of Paradise you 
    wish.’” This hadeeth was classed as saheeh by al-Albaani in Saheeh 
    al-Jaami’ al-Sagheer, no. 660. 

    Her patience in putting up with her husband’s marrying a 
    second wife will bring a special reward over and above that, for several 
    reasons: 

    1 – Her husband’s marrying another wife is regarded as a test 
    and trial for her, and if she bears that with patience she will have the 
    reward for being patient in the face of a trial, as Allaah says 
    (interpretation of the meaning): 

    “Only those who are patient shall receive their reward in 
    full, without reckoning”
    [al-Zumar 39:10]

    According to the hadeeth: “No fatigue, nor disease, nor 
    sorrow, nor sadness, nor hurt, nor distress befalls a Muslim, not even a 
    thorn that pricks him, but Allaah will expiate his sins thereby.” 

    Narrated by al-Bukhaari, 5642; Muslim, 2573, from the hadeeth 
    of Abu Sa’eed and Abu Hurayrah. 

    Al-Tirmidhi (2399) narrated from Abu Hurayrah that the 
    Prophet  (peace and blessings of Allaah be upon him) said: “Trials will 
    continue to befall the believer, man or woman, concerning himself, his child 
    and his wealth, until he meets Allaah with no sin on him.” Classed as saheeh 
    by al-Albaani in Saheeh al-Jaami’, no. 5815. 

    2 – If a woman accepts that and treats her husband and the 
    other wife well, she will have the reward of al-muhsineen. Allaah says 
    (interpretation of the meaning): 

    “Verily, he who fears Allaah with obedience to Him (by 
    abstaining from sins and evil deeds, and by performing righteous good 
    deeds), and is patient, then surely, Allaah makes not the reward of the 
    Muhsinoon (good‑doers) to be lost”
    [Yoosuf 12:90] 

    “Is there any reward for good other than good?”

    [al-Rahmaan 55:60] 

    “And verily, Allaah is with the Muhsinoon (good-doers)”

    [al-‘Ankaboot 29:69]

    3 – If she feels angry because of that, but she controls her 
    anger – and controlling one's tongue is part of controlling one's anger – 
    Allaah says (interpretation of the meaning): 

    “…who repress anger, and who pardon men; verily, Allaah 
    loves Al-Muhsinoon (the good‑doers)”

    [Aal ‘Imraan 3:134]

    This reward is in addition to the woman’s reward for obeying 
    her husband under ordinary circumstances. 

    A wise woman should accept whatever Allaah decrees for her, 
    and she should realize that her husband’s marrying another woman is 
    something permissible, so she should not object to it. It may be that this 
    (second) marriage will make him more chaste and prevent him from doing 
    something haraam. 

    It is very unfortunate that some women object less to their 
    husbands doing haraam things than to their marrying another woman in a 
    permissible manner. This is a sign of their lack of reason and religious 
    commitment. 

    Women should follow the good example of the wives of the 
    Prophet  (peace and blessings of Allaah be upon him) and his companions, 
    who were patient and sought reward even though many of them felt jealous. If 
    your husband goes ahead and takes a second wife then you have to be patient 
    and content and treat him well so that you can attain the reward of the 
    patient and the doers of good. 

    Note that this life is the life of trials and tests, and how 
    quickly it ends. So congratulations to the one who is patient in obeying Allaah in this life until he attains eternal delight in the gardens of Paradise. 

    And Allaah knows best.