Regarding His Rulings on Marriage and Matters Relating to it
Excerpt from the Book: Provisions for the Hereafter
by Ibn Qayyim
It has been authentically reported from him
that he rejected the marriage of a matron who had been given in marriage by her father against her will.
And in the 'Sunan', it is reported from him
that he allowed a virgin whose father had given her in marriage against her will to choose (whether or not she accepted the marriage).
And it has been authentically reported from him
that he said:"A virgin should not be married until her permission is sought and her permission is her silence." 
ruled that the orphan girl may be consulted and he said:"There is no orphanhood after puberty."
This proves the permissibility of marrying an orphan and it is proven by the Qur'an 
And also in the 'Sunan', it is reported from him
that he said:
"There is no marriage without (the consent of) a legal guardian." 
Also in the 'Sunan', it is reported that he
said:"A woman may not give herself in marriage, for it is the adulteress who gives herself in marriage." 
ruled that if a woman is given in marriage by two guardians, she is for the first (suitor). 
ruled regarding a man who had married a woman without fixing a dowry for her and who did not have sexual intercourse with her before he died, that she should have the same dowry as other women of her status, no less and no more, that she should have a share of his inheritance and that she must observe a waiting period ('Iddah) of four months and ten days 
In 'Sunan At-Tirmidhi', it is reported that he
said to a man:"Do you accept that I should marry you to so-and-so?"
He said: "Yes." Then he said to the woman:"Do you accept that I should marry you to so-and-so?"
She replied: "Yes." So he married them and the man consummated the marriage, but he had not fixed a dowry for her and he had not given her anything, so when death approached him, he compensated her with his share of the booty from Khaibar. 
These rulings imply the permissibility of marrying without naming a dowry, the permissibility of consummating the marriage before naming the dowry, the fixing of a dowry equal to that which other women of similar status receive, if the husband should die, even if he has not consummated the marriage, that she is obliged to observe the waiting period of death, even though he had not consummated the marriage; this was the view taken by Ibn Mas'ud
and the scholars of 'Iraq.
These rulings also imply the permissibility of taking the responsibility of giving both parties in marriage and that it is sufficient to say: "I have married so-and-so to so-and-so," restricting oneself to this.
commanded those who embraced Islam and had more than four wives to choose four of them. And he
ordered those who embraced Islam and had as wives two sisters to choose one of them. This implies the validity of the marriage of the disbelievers and that he should choose whom he wishes from the among those whom he married before embracing Islam and (if he retained less than four) from others after embracing Islam and that is the opinion of the majority of scholars. At-Tirmidhi has reported in a Hadeeth which he declared to be Hasan, that the Prophet
said:"If a slave marries without the permission of his masters, he is an adulterer."
 Narrated by Ahmad, on the authority of 'Abdullah Ibn 'Amr
 Narrated by Abu Dawud, on the authority of Abu Hurairah
 Narrated by Al-Bukhari, Muslim, At-Tirmidhi, An-Nasa'i, Ahmad and Ad-Darimi, on the authority of Abu Hurairah
 Narrated by Al-Bukhari, At-Tirmidhi, Abu Dawud, Ibn Majah, Ahmad and Ad-Darimi.
 Narrated by Ibn Majah, on the authority of Abu Hurairah
 Narrated by At-Tirmidhi, An·Nasa'i, Abu Dawud, Ahmad and Ad-Darimi, on the authority of Samurah Ibn Jundub
 Narrated by Muslim, At·Tirmidhi, An-Nasa'i, Abu Dawud and Ahmad.
 Narrated by Abu Dawud, on the authority of 'Uqbah Ibn 'Amir
 Narrated by At-Tirmidhi, Abu Dawud, Ahmad and Ad-Darimi, on the authority of Jabir Ibn 'Abdillah