What should the proxy of the woman’s guardian say when doing the marriage contract?
Question

If the father appoints a proxy to give his daughter in marriage, what should the proxy say to the groom when doing the marriage contract? If he says, “I give to you in marriage the woman on behalf of whom I am acting as a proxy” out of ignorance, is that valid? What is the correct phrase?
Praise be to Allah.If the father appoints a proxy to give his daughter in marriage, then this proxy should say words to indicate that he is acting as a proxy of the guardian in this marriage, such as saying “I give to you in marriage So-and-so the daughter of So-and-so, who has appointed me as his proxy to give her in marriage” or, “I give to you in marriage So-and-so the daughter of the one who has appointed me as his proxy,” and similar phrases.
Shaykh Ibn ‘Uthaymin (may Allah have mercy on him) said:
If the guardian has appointed a proxy, what the proxy should not say, for example, is, “I give to you in marriage my daughter.” Rather he should explain that he is a proxy, so he should say, “I give to you in marriage the daughter of So-and-so, who appointed me as his proxy, and she is So-and-so the daughter of So-and-so” or, “I give to you in marriage as a proxy the daughter of So-and-so the son of So-and-so.”
If he says: “I give to you in marriage the daughter of So-and-so,” that is not valid, because he has no guardianship over her, unless he explains the reason why he is giving the daughter of So-and-so in marriage, which is because he is his (the guardian’s) proxy."(Ash-Sharh al-Mumti‘  12/23).
Shaykh Ibn Jibrin (may Allah have mercy on him) said:
It is valid for the groom to appoint a proxy, and for the woman’s guardian to do so. Therefore if the groom is far away, he can send word appointing you as his proxy, and say: “You are my proxy in my marrying the daughter of So-and-so, so you should be present.” And the guardian of the girl may say: “I give my daughter in marriage to So-and-so, who has appointed you as his proxy.” And you may say: “I accept on behalf of So-and-so, who appointed me as his proxy.” That is valid.
Similarly, the guardian may appoint you as his proxy, so for example you may say to the groom: “I give to you in marriage the daughter of the one who appointed me as his proxy, So-and-so the daughter of So-and-so,” and he may say, “I accept.”(Sharh Akhsar al-Mukhtasrat).
As for the proxy of the guardian saying: “I give to you in marriage the woman on behalf of whom I am acting as a proxy,” this wording is not correct, because the woman has no right to do the marriage contract herself, or to appoint someone to do the marriage contract for her.
Rather her guardian should do the marriage contract for her on the basis of his having guardianship over her, not on the basis that he is acting as a proxy for her.
But usually people do not differentiate between these words, and do not pay attention to the difference in meaning or what they indicate.
Therefore what appears to be the case is that the marriage that was done with these words is valid, on the grounds of the intention of the guardian’s proxy, as he meant that he was the proxy of the guardian, not the proxy of the woman.
And Allah knows best.