Black magic (sihr) is something that definitely exists and causes harm to people. The Messenger of Allah (Allah bless him & give him peace) was also afflicted with black magic.
A Jew by the name of Labid ibn Asim who outwardly posed to be a believer (munafiq) carried out black magic on the Messenger of Allah (Allah bless him & give him peace). He took the hair of the Messenger of Allah (Allah bless him & give him peace) and made eleven knots and placed it under a rock in a well called Zarwan. The effect of this was that it created uncertainty in the mind of the Messenger of Allah (Allah bless him & give him peace) as to whether he had done or not done certain things (although this had no effect on his religious and prophetic obligations). At times the Messenger of Allah (Allah bless him & give him peace) felt he had accomplished something yet he had not done so and vice versa. The angel Jibra’il informed the Messenger of Allah (Allah bless him & give him peace) as to what had occurred and came down with the two Surahs, namely Surah al-Falaq and Surah an-Nas. The Messenger of Allah (Allah bless him & give him peace) together with the Companions (Allah be pleased with them all) went to the well and removed the knotted hair. As each verse was recited, the knots untied miraculously. At the eleventh knot, the Messenger of Allah (Allah bless him & give him peace) was relieved from the effects of this black magic. (See: Tafisir Ibn Kathir & Ma’arif al-Qur’an)
Thus, scholars mention that the recitation of the Mu’awwazatayn (the two Quls: al-Falaq and al-Nas) is very beneficial in the removing of and protection from black magic. One should make a habit of reciting these especially when retiring to bed and after the Fardh prayers. There are many virtues of these two Surahs mentioned in the Ahadith.
Sayyida A’isha (Allah be pleased with her) narrates that whenever the Messenger of Allah (Allah bless him & give him peace) would become ill, he would recite the Mu’awwizat (Surah al-Falaq & Surah an-Nas) and blow over himself. When his illness was aggravated, I used to recite these two Surahs (and blow my breath) over him and make him rub his body with his own hand, for its blessings. (Sahih al-Bukhari, no. 4728)
Apart from these two Surahs, the recitation of Surah al-Fatiha, Ayat al-Kursi, and last two verses of Surah al-Baqarah is also very beneficial.
Moreover, the famous Tibi’i Ka’b al-Ahbar (Allah be pleased with him) states: “Had it not been for the phrases that I recite regularly, the Jews would have turned me into a donkey (m: out of black magic). It was said to him: “What are these phrases?” He replied:
(Transliteration): “A’uzu bi wajhillah al-Adhim alladhi laysa shay’un a’dhamu minhu wa bi kalimatillah at-tammati allati la yujawizuhunna barrun wa la fajir wa bi asmaillah al-husna kulliha ma alimtu minha wa ma lam a’lam min sharri ma khalaqa wa bara’a wa zara’a.”
Translation: “I seek the protection of Allah the Great; He, than whom there is nothing greater. And I seek the protection of the perfect words of Allah which no man, virtuous or evil, can even transcend; and I seek the protection of all the beautiful names of Allah, those of them which I know and those which I do not know, from the evil of everything He (Allah) created, to which He has given existence, and which He has spread (over the earth or universe).”
(Recorded by Imam Malik in his al-Muwatta, 2/541, no. 2737)
Thus, the above supplication can be very beneficial in the removing of the effect of black magic.
Also, the consuming of Ajwa dates has been prescribed by the Messenger of Allah (Allah bless him & give him peace) as a remedy for black magic.
Amir ibn Sa’d narrates from his father that the Messenger of Allah (Allah bless him & give him peace) said: “He who eats seven Ajwa dates every morning, will not be affected by poison or magic on the day he eats them.” (Sahih al-Bukhari, no. 5130)
The above are just some of the methods in removing the effect of black magic that have been prescribed in the Sunnah, thus one may resort to any of them. There are also other remedies besides the above, but time does not allow me to mention them all.
Finally, before parting, I would like to state that undoubtedly black magic is something that exits but it is observed that many people experience some type of downfall or illness and quickly jump to the conclusion that somebody has carried out black magic and start pointing fingers at others. If a child refuses to marry someone whom the parents want him/her to marry, then the parents begin to regard it to be the cause of black magic. Similarly, if the relations of the husband and wife turn sour, the first assumption is that it must be black magic that was carried out by such and such person. Black magic is regarded to be the cause behind every minor and major illness.
This type of understanding is incorrect. One should not be too hasty in concluding that the cause of a problem is black magic, because more often than not, black magic has nothing to do with the problem.
Secondly, due to this, many people have made it a business, in that they deceive people in making them believe that they have some sort of black magic done upon them, thus they are charged with a massive sum for the treatment. People have made thousands in this business.
Thus, one should be very careful in these matters, for in it rests the benefit of this world and the hereafter. Do not be too hasty in determining that the cause behind the problem is black magic. However, if there is substantial evidence such as the sudden break of illness, etc, then one may determine whether it is the cause of black magic or otherwise. And in the case of being afflicted with it, one must primarily turn to Allah Most High and resort to the remedies mentioned in the Qur’an and Sunnah. Also, if the help of others is sought, then one should only turn to those who are God-fearing and pious.
May Allah Most High guide us all towards the right direction, Ameen.