A muslim women marries non muslim man and on the death of that women , Question: 1) can imaam prays the funeral namaaz of that lady?2) can hindu relatives and her hindu husband can involve in janaza namaaz?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.

It is well-known that it is prohibited for a Muslim woman to marry a non-Muslim man, and if she does, such a marriage is invalid according to the scholarly consensus. Allaah The Exalted says (what means): {And do not marry polytheistic men [to your women] until they believe. And a believing slave is better than a polytheist, even though he might please you. Those invite [you] to the Fire, but Allaah invites to Paradise and to forgiveness, by His permission. And He makes clear His verses to the people that perhaps they may remember.} [Quran 2:221]

At-Tabari commented on this verse saying: "It means that Allaah The Exalted has forbidden believing women from marrying non-Muslim men, regardless of their religion. Muslim women should marry Muslim men only; non-Muslim men are unlawful to them."

Al-Qurtubi reported a scholarly consensus concerning, saying: "The Muslim community has unanimously agreed that a non-Muslim is not entitled to inherit from a Muslim relative and it is forbidden for a Muslim woman to marry a non-Muslim man."

As for your question regarding the funeral prayer for this woman: if she married him while considering such a marriage to be lawful despite knowing that it is forbidden in the Islamic religious law, then she is an apostate for legalizing something that Allaah has made unlawful. This removes her from the fold of Islam. Shaykhul-Islam Ibn Taymiyyah said: "Whoever declares to be lawful something that is unanimously agreed-upon as unlawful, or declares to be unlawful something that is unanimously agreed-upon as lawful, or alters the agreed-upon Islamic law, then he is a disbeliever and an apostate according to the scholarly consensus."

If it is decided that she is a disbeliever, then it is impermissible for Muslims to perform funeral prayer for her and she must not be buried with Muslims in a Muslim cemetery.

On , if she got married to this non-Muslim man but she did not know the Islamic law regarding this sinful act, or she did so because she was following her sinful desires while believing in the unlawfulness of such an act, then she is considered a sinner: common Muslims should perform funeral prayer for sinners when they die, but people of knowledge and virtue should not join the funeral prayer in order to deter Muslims from following their example. For more benefit, please refer to Fatwa 159467.

However, a non-Muslim cannot join the funeral prayer. If it is impermissible for a Muslim to join the prayer without performing the required purification (ablution), then what about a disbeliever who is ritually impure as he does not purify himself from minor or major impurities! There is no room for flattery when it comes to the prayer.

When the Maaliki scholar ‘Ulaysh was asked about a judgment on a Thimmi (non-Muslim living in the Muslim community) following the funeral of a Muslim person. The question was "What do you say about a Thimmi following a Muslim's funeral procession; should Muslims prevent him from following the funeral procession?"

He answered: "Yes, they may prevent him from doing so because he is ritually impure; Allaah The Exalted says (what means): {Indeed, the polytheists are unclean.} [Quran 9:28] Moreover, he is in a state of Janaabah (major defilement) and the Angels of mercy do not go near a person who is in a state of Janaabah. In addition, the whole point of joining the funeral is to intercede with Allaah on behalf of the dead person; the non-Muslim cannot intercede with Allaah on behalf of a Muslim because he is an enemy of Allaah, and he is removed from Allaah's mercy. Moreover, it has been reported that one of the rewards for attending a funeral is having one's sins forgiven; a disbeliever is not worthy of such forgiveness. Allaah The Exalted says (what means): {Indeed, Allaah does not forgive association with Him, but He forgives what is less than that for Whom He wills>} [Quran 8:48]

In addition, attending the funeral is a collective religious duty (i.e. a duty which, if performed by some, exempts others from performing it. However, if it is not performed by any, the entire community is sinful), and it is an obligatory Islamic rite, which the non-Muslim is unworthy of participating in. These are some of the clear reasons that are known to anyone who is well acquainted with the laws of Islam, and Allaah knows best. May peace and blessings be upon the Prophet, sallallaahu ‘alayhi wa sallam, and his family."

Since disbelievers should be prevented from following the funeral procession, they should be prevented from standing in the prayer rows in the funeral prayer with even greater reason. The best thing to be done in this regard is for the Muslim to perform the funeral prayer for his dead Muslim brother and explain the impermissibility of non-Muslims attending the funeral; the Imaam of the funeral prayer may announce that.

Allaah Knows best.