Aoa wr wb... me and my bf have been together for more than 1 year... he has sworn on Allah to marry me... but when he spoke to his parents, he came to know that 12 years ago his parents have given commitment elsewhere for his marriage... according to islam, what is he supposed to do? Maintain his promise with me or leave me to marry the girl chosen by his parents?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

If you mean that you have loved each other for a year during which you were careful to avoid what does not please Allah, The Exalted, such as being together in seclusion or engaging in intimacy and the like, there is nothing wrong with that. But if you mean that you were involved in an illegitimate affair, then you must end this relationship, as it is similar to the taking of secret lovers that prevailed in the pre-Islamic era of ignorance, which Islam prohibited. Allah, The Exalted, Says (what means):

• {…desiring chastity, not unlawful sexual intercourse or taking [secret] lovers…} [Quran 5:5]

• {[They should be] chaste, neither [of] those who commit unlawful intercourse randomly nor those who take [secret] lovers…} [Quran 4:25]

Marriage is the best solution for those in love, as stated in the Hadeeth narrated by Ibn Maajah on the authority of Ibn ‘Abbaas who related that the Messenger of Allah, sallallaahu ‘alayhi wa sallam, said: "There is nothing better than marriage for those who are in love."

It is not incumbent on this man to obey his parents regarding marrying this woman if he has no desire to marry her.

Shaykhul-Islam Ibn Taymiyyah said in Al-Fataawa Al-Kubra: “The parents have no right to compel their son to marry a woman he does not wish to marry. He is not considered undutiful (if he refuses), for it is the same as the case when he refuses to eat what he does not wish to eat.” [End of quote]

On the other hand, it is not permissible for him to disobey his parents and marry you if they refuse that. Obedience to his parents is obligatory on him, but his marriage to a certain woman, whether it is you or someone else, is not obligatory on him. What is obligatory takes precedence over what is not, as long as the man does not fear for himself to fall into sin because of this love; otherwise, he should give priority to preserving his chastity.

Ibn Muflih said in Al-Aadaab Ash-Shar‘iyyah: “Imaam Ahmad said: ‘If a man fears for himself to fall into sin, and his parents prevent him from marriage, they have no right to do so.’ A man said to him: ‘I have a slave girl, and my mother asks me to sell her.’ He said: ‘Do you fear that you will remain emotionally attached to her?’ The man said: ‘Yes.’ He [Imaam Ahmad] said: ‘Do not sell her!’ He said: ‘My mother says: ‘I will not be pleased with you unless you sell her!’ He said: ‘If you fear for yourself, then she has no right to ask this of you.’” [End of quote]

On the other hand, scholars held different opinions regarding the ruling on fulfilling promises. The preponderant opinion is the view maintained by the majority of scholars, that it is recommended but not an obligation.

Finally, if it is not possible for him to marry you, then you should not remain emotionally attached to him but ask Allah, The Exalted, to bless you with someone better instead, and delegate your affairs to Him, for He is more knowledgeable of the consequences of all matters. He Says (what means): {But perhaps you hate a thing and it is good for you; and perhaps you love a thing and it is bad for you. And Allah Knows, while you know not.} [Quran 2:216]

It is incumbent on this man to expiate his oath if he breaks it by not marrying you. He has the choice either to feed ten poor people or clothe them. If he is unable to do that, he is required to fast for three days. However, it is invalid to opt for fasting and skip the first two choices unless he is unable to feed or clothe ten poor people.

Allah Knows best.