Assalamualaikum ustaz. I once witnessed a person treating a patient by holding a séance. So, what is the ruling of treatment using this method? Hope for an explanation.
Waalaikumussalam wrt. wbt.,
Alhamdulillah, praise and gratitude to Allah SWT for His countless blessings for us all. Praise and salutations to our beloved Prophet Muhammad PBUH, his family, companions, and all those who follow his footsteps until the Final day.
We start this discussion by citing the opinions of scholars related to the Islamic alternative treatment. In the context of alternative treatment in Malaysia, it is commonly known as a person practising ruqyah and involved in alternative or complementary treatment that completed modern treatment.
Syeikh Jibrin in his fatwa stated: “Actually, it is permissible to practise ruqyah for whoever has a good recitation, understands its meaning, have a correct faith and great character and conduct. It isn’t conditioned for the person who is performing the treatment to know all the furu’ (branched) issues in the religion and learn it in-depth.
This is based on the story of Abu Said who treated a person who was stung. He said: “We never knew that (surah al-Fatihah) is a verse for treatment or as stated in the hadith narrated by al-Bukhari and Muslim.” A person who is performing the treatment must have a good intention and to benefit other Muslims as well as not wanting to get wealth and rewards so that the verses recited will be more effective.” 
As for Islamic treatment such as the process of treatment by reciting verses of the Quran such as ruqyah and others, then it must follow the conditions of treatment. The reason is to differentiate between ruqyah that follows sunnah with ruqyah that contradicts sunnah.
Here, we cite three conditions stated by Imam al-Hafiz Ibn Hajar al-Asqalani, among others states: “Scholars have agreed on the permissibility of treatment that fulfils these three conditions:
- Ruqyah must be done using the statements of Allah SWT or with any of His names and attributes.
- Ruqyah is performed in Arabic or a language other than Arabic of which its meaning are understood.
- Must believe that the ruqyah doesn’t affect anything except with the permission of Allah SWT. 
Imam al-Nawawi also stated regarding this issue, he said: “Ruqyah that should be left are incantations that were recited that originated from the speech of the disbelievers, strange incantations, treatment with spells or incantations of which their meanings are unknown. All of these are impermissible, for there is a possibility that it means disbelief or close to disbelief or makruh.
As for treatments using verses of the Quran and dhikrs of which their meanings are understood are permissible and even a sunnah. Scholars cited the agreed opinion that it is permissible to perform treatments using the verses of the Quran and dhikrs to Allah SWT.” 
Imam al-Syaukani said: “Ruqyah with Allah SWT’s book is permissible and it is followed with dhikrs and ma’thur supplications, supplications that aren’t ma’thur is also permissible as long as they don’t contradict with ma’thur supplication.” 
The issue of holding a séance in treatment
Coming back to the above question, a séance is a situation when a person is possessed with a jinn or jinns, making the individual semi-conscious or unconscious. The rituals or actions afterwards depends on the purpose the séance is held.
The séance can be understood to be in three forms: tahdir al-arwah (presentment of a soul) or tanasukh al-arwah (changing of soul / reincarnation) and istinzal al-arwah. The shaman or medium who is performing the treatment will “change” into “another individual” with a different voice and character. Some will introduce themselves as the king of the elves, warriors, certain wali or prophets.
Citing from the fatwa issued by Syeikh Mutawalli al-Sya’rawi regarding the practice of tahdir al-arwah, he said that it doesn’t have a basis from the Quran and sunnah and is just a deception. 
Allah SWT states:
وَقَيَّضْنَا لَهُمْ قُرَنَاءَ فَزَيَّنُوا لَهُمْ مَا بَيْنَ أَيْدِيهِمْ وَمَا خَلْفَهُمْ وَحَقَّ عَلَيْهِمُ الْقَوْلُ فِي أُمَمٍ قَدْ خَلَتْ مِنْ قَبْلِهِمْ مِنَ الْجِنِّ وَالْإِنْسِ إِنَّهُمْ كَانُوا خَاسِرِينَ
“And We appointed for them companions who made attractive to them what was before them and what was behind them [of sin], and the word has come into effect upon them among nations which had passed on before them of jinn and men. Indeed, they [all] were losers.” 
Asking for help from the jinn is a form of shirk to Allah SWT. Although they may be effective (by the will of Allah), the practice still contradicts syarak according to the above verse. Jinn and shaytan will try their best to deviate people in any way possible even more so if it may seem good and does not contradict Islam.
Allah SWT states:
وَأَنَّهُ كَانَ رِجَالٌ مِنَ الْإِنْسِ يَعُوذُونَ بِرِجَالٍ مِنَ الْجِنِّ فَزَادُوهُمْ رَهَقًا
“And there were men from mankind who sought refuge in men from the jinn, so they [only] increased them in burden.” 
In our opinion, the practice of holding a séance is shirk and prohibited. Whoever was ever involved should repent to Allah SWT.
The 25th Aqidah Study Panel Meeting/2003 of the Department of Islamic Development Malaysia (JAKIM) has decided that the practice of tahdhir arwah is illegal.
We call on Muslims to abandon practices that lead to shirk and superstition and believe in them. Efforts made to treat any problem or disease must follow the requirements of syarak.
 See al-Lu’lu al-Makin, pg. 22
 See al-Fath al-Bari, 10/240
 See Syarh al-Nawawi ‘ala Sahih Muslim, 14/141-142
 See Nail al-Autar, 10/440
 See al-Fatawa, pg. 19
 Surah Fussilat: 25
 Surah al-Jin: 6