In the name of Allah, the Gracious, the Merciful
It is permissible for Muslims to attend the funeral processions of non-Muslims and to offer condolences to their families and friends, as long as one does not participate in rituals specific to their religion or pray for the deceased non-Muslims to be admitted into Paradise. We should empathize with other people when they are suffering, while at the same time we need to respect the boundaries imposed by our faith.
Several of the righteous predecessors allowed Muslims to attend the funerals of non-Muslim citizens and relatives, but without becoming too closely involved in their rituals.
Muhammad ibn Musa reported: I said to Abu Abdullah, “Can a Muslim escort the funeral of an idolater?” Abu Abdullah said:
نَعَمْ
Yes
Abu Talib reported: I asked Abu Abdullah about a man who dies as a Jew and he has a Muslim son. What should he do? Abu Abdullah said:
يَرْكَبُ دَابَّتَهُ وَيَسِيرُ أَمَامَ الْجِنَازَةِ وَلَا يَكُونُ خَلْفَهُ فَإِذَا أَرَادُوا أَنْ يَدْفِنُوهُ رَجَعَ مِثْلَ قَوْلِ عُمَرَ
He should ride his animal and march in front of the funeral, not behind it. When they intend to bury him, let him return back. Such is the opinion of Umar.
Source: Aḥkām Ahl al-Dhimmah 1/432-433
Sa’id ibn Jubayr reported: I asked Ibn Abbas, may Allah be pleased with him, about a man whose father died as a Christian. Ibn Abbas said:
يَشْهَدُهُ وَيَدْفِنُهُ
He may witness it and bury him.
Source: Aḥkām Ahl al-Dhimmah 1/437
It is recommended to stand for funerals out of respect for human life and so as not to offend the living.
Amir ibn Rabia reported: The Messenger of Allah, peace and blessings be upon him, said:
إِذَا رَأَيْتُمْ الْجَنَازَةَ فَقُومُوا لَهَا حَتَّى تُخَلِّفَكُمْ أَوْ تُوضَعَ
When you see a funeral procession, then stand up for it until it passes or the deceased is placed in the grave.
Source: Sahih Bukhari 1245, Grade: Muttafaqun Alayhi
Some scholars said this command was abrogated and thus standing is prohibited or merely permissible, although others held it to be a general recommendation.
Al-Nawawi writes:
وَاخْتَارَ الْمُتَوَلِّي مِنْ أَصْحَابِنَا أَنَّهُ مُسْتَحَبٌّ وَهَذَا هُوَ الْمُخْتَارُ فَيَكُونُ الْأَمْرُ بِهِ لِلنَّدْبِ وَالْقُعُودُ بَيَانًا لِلْجَوَازِ
The preferred opinion of Al-Mutawalli among our scholars is that standing for a funeral is recommended. This preference is command by way of encouragement, yet sitting is clearly permissible.
Source: Sharḥ al-Nawawī ‘alá Ṣaḥīḥ Muslim 958
We do not have to particularly like the deceased person or agree with what they did in life in order to respect the funeral process. Respecting funerals is in reality an act of respect to Allah, who oversees life and death.
Qays ibn Sa’d reported: A funeral passed by the Messenger of Allah, peace and blessings be upon him, and he stood up. It was said to him, “It is a Jew.” The Prophet said:
أَلَيْسَتْ نَفْسًا
Was he not a soul?
Source: Ṣaḥīḥ al-Bukhārī 1250, Grade: Muttafaqun Alayhi
In another narration, the Prophet said:
إِنَّمَا تَقُومُونَ إِعْظَامًا لِلَّذِي يَقْبِضُ النُّفُوسَ
Verily, you only stand to glorify Allah, who is the receiver of souls.
Source: Musnad Aḥmad 6394
Hence, death itself is something to be respected regardless of who the deceased persons are.
It is further permissible to send condolences and good wishes to the family members and friends of deceased non-Muslims.
Ibn al-Qayyim reported: Hasan al-Basri, may Allah have mercy on him, said:
إِذَا عَزَّيْتَ الذِّمِّيَّ فَقُلْ لَا يُصِيبُكَ إِلَّا خَيْرٌ
If you console a non-Muslim citizen (dhimmi), then say: May nothing beset you but goodness.
Huraym reported: I heard al-Ajlah, may Allah have mercy on him, console a Christian and he said:
عَلَيْكَ بِتَقْوَى اللَّهِ وَالصَّبْرِ
You must be mindful of Allah and be patient.
Mansur reported: Ibrahim, may Allah have mercy on him, said:
إِذَا أَرَدْتَ أَنْ تُعَزِّيَ رَجُلًا مِنْ أَهْلِ الْكِتَابِ فَقُلْ أَكْثَرَ اللَّهُ مَالَكَ وَوَلَدَكَ وَأَطَالَ حَيَاتَكَ
If you intend to console a man from the people of the Book, then say: May Allah increase your wealth and children and lengthen your life.
Harb reported: I said to Ishaq, may Allah have mercy on him, “How is an idolater consoled?” Ishaq said:
يَقُولُ أَكْثَرُ اللَّهُ مَالَكَ وَوَلَدَكَ
It is said: May Allah increase your wealth and children.
Source: Aḥkām Ahl al-Dhimmah 1/438
As such, we have two broad concerns when it comes to non-Muslim funerals which need to be balanced. First, we ought to show respect, compassion, and empathy to the living as good examples of Islam and in furtherance of positive community relationships. Second, we need to respect the limits imposed by our faith in not participating in non-Muslim rituals or praying for the salvation of the deceased.
Dying upon a religion besides Islam is an enormously consequential matter and our abstention from participating in non-Muslim rituals, although done in a respectful manner, ought to communicate the seriousness with which we practice our faith.
Success comes from Allah, and Allah knows best.