Is the father or mother-in-law's brother mahram?
Well, first you need to understand what the term
mehram means. It means the person with whom marriage is not allowed. We people now a days confuse our selves by thinking that the
mehram means the person who we can chat out with. I have heard some fellow saying this which I never knew at that time that it is wrong. I will try to be using simple english instead.
Father is someone, who is male and is involved in our birth. Which means there is a relation of us with him by blood. So we cannot marry him, which means that he cannot be married to the person having a blood-relation with, making him a
mehram for his daughters.
Do you have a relation with him? No. How? Have a look below.
You married someone, whose mother's brother has no relation directly to the person who you married. If you meant to say Mother-in-law then she was a
mehram for you, since she is having a blood-relation to the spouse. But other relations are not
You need to consider some other points too, such as if mother-in-law's brother was fed milk by the same female by whom you were fed, then you're having a
mehram relation to him too.
In-law mahrams with whom one becomes mahram by marrying someone: father-in-law, mother-in-law; son-in-law, daughter-in-law, stepfather (mother's husband) if their marriage is consummated, stepmother (father's wife) if their marriage is consummated; stepson (husband's son) if their marriage is consummated, stepdaughter (wife's daughter) if their marriage is consummated;
Of course they are mahrams! And this is stated in the Quran, Surat An-Nisā' 4:23:
Prohibited to you [for marriage] are your mothers, your daughters, your sisters, your father's sisters, your mother's sisters, your brother's daughters, your sister's daughters, your [milk] mothers who nursed you, your sisters through nursing, your wives' mothers, and your step-daughters under your guardianship [born] of your wives unto whom you have gone in. But if you have not gone in unto them, there is no sin upon you. And [also prohibited are] the wives of your sons who are from your [own] loins, and that you take [in marriage] two sisters simultaneously, except for what has already occurred. Indeed, Allah is ever Forgiving and Merciful.