What is wali and who is a wali in marriage

 What is wali and who is a wali in marriage.

ALHAMDULILLAH, wali means guardian or someone who rrpesenr something.

This is one of the on obligatory thing marriage cannot take place without it.

Allah says in Qur'an,

An-Nisa' 4:25

And whoever among you cannot [find] the means to marry free, believing women, then [he may marry] from those whom your right hands possess of believing slave girls. And Allah is most knowing about your faith. You [believers] are of one another. So marry them with the permission of their people and give them their due compensation [i.e., mahr] according to what is acceptable. [They should be] chaste, neither [of] those who commit unlawful intercourse randomly nor those who take [secret] lovers. But once they are sheltered in marriage, if they should commit adultery, then for them is half the punishment for free [unmarried] women. This [allowance] is for him among you who fears affliction [i.e., sin], but to be patient is better for you. And Allah is Forgiving and Merciful.

Marry them with the leave of their wali(people in charge of them).

The wali of a person should be from father's side.

Abu Musa r.a narrated saying,

the Messenger of Allah said: "There is no marriage except with a Wali.

Reference : Jami` at-Tirmidhi 1101

In-book reference : Book 11, Hadith 22.

The wali is not necessary to be a father but a judge(qadi) or Muslim who is just, a person who is known of His good character can be a wali if the father object to the marriage without any valid reason.

The wali is the one in case a problem happens in the marriage will be the one to stand for the lady.

And Islam does not allow marriage to take place without such person so to avoid any problem in future of who to stand for the woman.

May Allah guides our eeman. Aamin