He said to his wife: “You are to me like my mother”
Question

                A woman’s husband said to her: “You are to me like my mother.” Is this regarded as a talaaq divorce or is there expiation for it? What is the expiation?.
Praise be to Allah.Firstly: 
This phrase 
    is not regarded as a talaaq divorce, rather it is a kind of zihaar [a 
    jaahili form of divorce in which the husband says to his wife, “You are to 
    me as my mother’s back”] which is not explicitly zihaar, rather it may be 
    understood as zihaar or as something else. 
Secondly: 
The ruling 
    on this phrase depends on the intention of the speaker (the husband) and the 
    context. 
As for the 
    intention, if the husband intended by saying that that she was forbidden to 
    him like his mother, then it is zihaar. 
Or he may 
    have meant that she is like his mother in honour and love etc, in which case 
    it is not zihaar, and does not mean anything.  
As for 
    context, if the context of words and events that came before this indicate 
    that the husband intended zihaar, then it is zihaar. Examples of such 
    contexts are: if the husband was having an argument with his wife and during 
    that argument he said, “You are to me like my mother.” This context suggests 
    that he intended zihaar so it is zihaar, 
Shaykh 
    al-Islam Ibn Taymiyah was asked in Majmoo’ al-Fataawa (34/5) about a 
    man who said to his wife: “You are to me like my mother or my sister.” He 
    replied: If what he meant was you are to me like my mother or my sister in 
    terms of honour, then he does not have to do anything, but if what he meant 
    was likening her to his mother or sister in terms of marriage, then this is 
    zihaar and he has to do the same as the one who divorces his wife by zihaar: 
    if he chooses to keep her, he should not approach her until he has offered 
    the expiation for zihaar.  End quote. 
He also said 
    (34/7): 
If he meant 
    when he said, “you are like my mother to me” that he would refrain from 
    physical relations with her which are forbidden in the case of the mother, 
    then this is zihaar and he is obliged to do what the man who divorces his 
    wife by zihaar is obliged to do. It is not permissible for him to have 
    intercourse with her until he has offered the expiation for zihaar, namely 
    freeing a slave. If that is not possible then he must fast for two 
    consecutive months. If he cannot do that then he must feed sixty poor 
    persons. End quote. 
Ibn Qudaamah 
    said in al-Mughni (11/60): 
If he says: 
    You are to me like my mother, intending zihaar thereby, then it is zihaar, 
    according to the majority of scholars, including Abu Haneefah and his two 
    companions, al-Shaafa’i and Ishaaq. If he intended thereby to show honour 
    and respect, or to say that she is like her in age or in some other way, 
    then this is not zihaar. What matters is what he says about his intention. 
    End quote. 
i.e., the 
    husband is the one who has to clarify what he intended. 
It says in
    Fataawa al-Lajnah al-Daa’imah (20/274): 
If the 
    husband says to his wife: I am your brother or You are my sister or You are 
    my mother or like my mother, or You are to me like my mother or my sister, 
    if he means thereby that she is like them in honour, family ties or respect, 
    or he did not have any particular intention, or there is no context to 
    suggest that he intended zihaar, then this does not result in zihaar and he 
    does not have to do anything. But if he intended zihaar with these or 
    similar words, or there is a context that indicates zihaar, such as these 
    words being uttered in anger or as a threat to her, then it is zihaar. This 
    is haraam and he must repent, and also offer expiation before he touches 
    her. The expiation is to free a slave; if that is not possible then he must 
    fast for two consecutive months. If he cannot do that then he must feed 
    sixty poor persons. End quote. 
To sum up: 
If the 
    husband intended zihaar by these words, or if there is a context that points 
    to that, then it is zihaar. If it is other than that, then it is not zihaar 
    and he does not have to do anything. 
Thirdly: 
Zihaar is 
    haraam, and Allaah has described it as an ill word and a lie, and He says 
    (interpretation of the meaning): 
“Those 
    among you who make their wives unlawful to them by Zihaar (i.e., by saying 
    to them “You are like my mother’s back,”) they cannot be their mothers. None 
    can be their mothers except those who gave them birth. And verily, they 
    utter an ill word and a lie”

    [al-Mujaadilah 58:2]
The one who 
    speaks the words of zihaar to his wife has to repent to Allaah, may He be 
    exalted.
Fourthly: 
The husband 
    who divorces his wife by zihaar has to offer expiation if he wants to keep 
    her and not divorce her and it is not permissible for him to have 
    intercourse with her until he has offered expiation. The expiation is to 
    free a slave. If that is not possible then he must fast for two consecutive 
    months. If he cannot do that then he must feed sixty poor persons. The 
    evidence for that is the verse in which Allaah says (interpretation of the 
    meaning): 
“And 
    those who make unlawful to them (their wives) by Zihaar and wish to free 
    themselves from what they uttered, (the penalty) in that case is the freeing 
    of a slave before they touch each other. That is an admonition to you (so 
    that you may not repeat such an ill thing). And Allaah is All‑Aware of what 
    you do.
4. And he 
    who finds not (the money for freeing a slave) must fast two successive 
    months before they both touch each other. And he who is unable to do so, 
    should feed sixty Masaakeen (poor). That is in order that you may have 
    perfect faith in Allaah and His Messenger. These are the limits set by 
    Allaah. And for disbelievers, there is a painful torment”

    [al-Mujaadilah 58:3-4].