The essence of prostration is humility and it is one of the obligations we must perform, as the Quran says: “O you who have faith! Bow down and prostrate yourselves…”.
There is an important point here that must be kept in mind, and that is that the Shia prostrate on soil, not for the soil, because prostration for other than Allah is shirk (polytheism) according to all Shia scholars.
Sometimes it is asked why we prostrate only on soil. The answer is that regarding this issue, we follow the tradition and way of the prophet (pbuh); Sunni sources tell us that prostration has to be on soil and after that, on anything that grows from the earth, given that it isn't something that is considered wearable or edible, although, in extenuating circumstances, it is permissible to even prostrate on those too!
For each of these cases, we will mention a hadith, and leave the details to the detailed answer.
1- Prostrating on soil: In his Sahih, Muslim says: (Allah) made the earth a place of prostration for us and a means of ablution when there is no water.
2- Prostrating on what grows from the earth: Bukhari reports in his Sahih: Umm Salim requested the prophet (pbuh) to come to her home and pray there, so that she would make that same spot her permanent place of worship. The prophet accepted and came there, spread out a straw mat she had in her home, I dampened it and he prayed there, and Umm Salim prayed along with him and made it her praying place [from then on].”
3- Prostrating on clothing in extenuating circumstances: Bukhari narrates from Anas bin Malik: We (the Muslims) would pray with the prophet (pbuh), and because of the degree of heat, would place a part of our clothing on where we would prostrate, and would prostrate on that.
Therefore, as you can see, in this issue, the Shia rely on the tradition of the prophet that has also been narrated in Sunni sources.
The question that awaits answering, is why the Shia prostrate on the soil of the grave of Imam Husayn (as).
In response to such a question, one must say that firstly, this soil is just like every other soil in the fact that it is soil, and shouldn’t be isolated from other soils. Secondly, it isn't mandatory to prostrate on this particular soil, rather it is recommended. Third of all, the reason for why the Shia prostrate on the soil of Imam Husayn’s grave is because it is something the Ahlul-Bayt have emphasized has great rewards.
Fourth of all, soil, especially from the grave of Imam Husayn (as), symbolizes matters of faith, resistance, history, etc., and this is also another reason for such.
It is narrated that Imam Sadiq (as) was asked about the philosophy of prostrating on soil, the imam (as) answered: “Prostration is humility before Allah (swt). So it isn't befitting that it be done on edible and wearable things, the reason being that the people of the world are slaves of food and clothing, while the one prostrating is [supposed to be] a servant of Allah’s during prostration, so it isn't appropriate for one to put his forehead on something others are a slave of, those who have been deceived by this world. Prostrating on soil is higher, because this is more expressive of one’s humility towards Allah.”
One of the controversial issues used against the Shia, out of animosity or ignorance, which is presented by their opposers, is the issue of prostrating on soil. This is while if this issue is explained and analyzed fairly and the way it really is, it will be exactly the opposite of what is being attributed to the Shia. The reason being that the Shia prostrate on soil and not for it; prostration is of two types: prostrating on something, and prostrating for something.
Without a doubt, the second is a form of shirk (polytheism) and the Shia see this to be haram and forbidden and we refer you to the fatwas (legal verdicts) of Shia scholars in this regard, you can see for yourself.
To clarify the issue, we will analyze it in the following lines.
Definition of sujud (prostration):
The lexical meaning of sujud is humility. In holy Islamic law, it means to put a part of the forehead on the ground without any obstacle between the forehead and the ground. The evidence for this is a hadith that reads: “When you prostrate, place your forehead on the ground and don’t poke it to the ground quickly.”
There is also another hadith in this regard: “We complained to the prophet (pbuh) about the heat of the ground of Makkah and Madinah on our foreheads and hands, but the prophet didn’t give our complaint a positive answer [he didn’t make any change in the rite].”
There is a consensus amongst all scholars and jurists that sajdah is an obligation, because of the verse: “O you who have faith! Bow down and prostrate yourselves…”.
The legality of this issue
It is obvious that this issue is a legal one and not theological, because prostration is an action that one does and actions are the subject of legal rulings and not theology. Difference of opinion in legal issues (both in the Shia and Sunni schools of thought) is very common, the best reason for such a claim is the fact that there are four schools of Sunni thought that have different views on various legal issues.
The hadiths on the subject of prostration
The hadiths on this subject can be divided into three categories:
1- Narrations that emphasize the necessity of prostrating on earth.
2- Narrations that speak of prostration on plants, such as straw.
3- Narrations pointing to prostration on cotton or wool clothing (cloth).
a) Narrations that emphasize prostration on earth: These hadiths are many in number with different phrasing; here we will mention several examples:
1- “جعلت لی الارض مسجداً و طهوراً” (Earth was made a place of prostration and a means of ablution for me). This hadith has been mentioned in the Sahih of Muslim like this:
“All earth has been made a place of prostration for us, and its soil a means of ablution when there is no water.”
and in the Sunan of Tirmidi like this:
“All earth has been made a place of prostration for us and a means of ablution.”
and in the words of Beyhaqi like this:
“Earth was made a place of prostration and a means of ablution for me.” and also like such: “Earth was made pure and a place of prostration for me and when the time for prayer arrives, I will pray, no matter where it is.”
2- AbuDhar quotes the prophet (pbuh) saying: “Earth is a place of prostration for you. So wherever you are, when the time for prayer arrives, go ahead and pray.”
3- Ibn Abbas says: “The prophet prostrated on stone.”
4- Abu Sa’eed Khudri narrates: “I saw traces of mud and soil on the forehead of the prophet with my own eyes.”
5- Jabir ibn Abdillah says: “I was praying dhuhr with the prophet (pbuh). Because of the intense heat and temperature, I kept a stone in my hand so it would cool off so that I could prostrate on it.”
6- Anas bin Malik says: “We would pray with the prophet under intense heat, and would each pick up a stone and hold it in our hand so it would cool down, and when it did, we would prostrate on it.”
7- Umar bin Khattab says: “We came out on a rainy night for the morning prayer, we each picked some rocks and carpeted the mosque’s floor with them and prayed on them. When the prophet (pbuh) noticed this, he said: “What a good thing [you did]. It was since then that prostrating on stone began.”
8- Ayad bin Abdillah Qurashi narrates: “When the prophet saw a man prostrating with the turban he had on, he signaled him to push the turban back and prostrate on his [bare] forehead.”
These were a few examples of the many hadiths that tell us to prostrate on soil and earth. Beyhaqi says: “…If prostrating on cloth and clothing was permissible, it would have been pointed to in the hadiths, because it is much easier than picking up a stone and holding it in the hand until it cools off [but nothing has been mentioned of it and this shows its impermissibility].”
b) Hadiths that say it is permissible to prostrate on other than earth in extenuating circumstances:
1- Anas bin Malik narrates: “His grandmother (Malikah) invited the prophet to a meal she had cooked for him. The prophet ate from it and said: “Rise and pray with me.” Anas says: “I rose up and sprinkled water on and dampened a straw mat that had blackened over time. The prophet (pbuh) stood on it, with me behind him and the old lady (his grandmother) behind me.”
Anas bin Malik has also been reported saying: “One of my aunts cooked a meal for the prophet (pbuh) and addressed him saying: “I would really like it if you have this meal at my place and also pray there!” Anas says: “The prophet (pbuh) came and ordered that we spread a big straw mat we had in the home in a corner. We did so and sprinkled some water on it and swept it. The prophet (pbuh) then prayed on it while we prayed behind him.”
In another narration by Anas bin Malik, he says: “Umm Salim asked the prophet (pbuh) to come to her home and pray there, so that she could make it her permanent place of worship. The prophet (pbuh) fulfilled this request of Umm Salim’s and came to her home. I dampened a straw mat that was there with water and the prophet prayed there with Umm Salim praying along with him. She made that place her place of worship from then on.”
2- Ibn Abbas narrates: “The prophet of God would pray on a straw mat.”
3- Abu Sa’eed Khudri relates: “I entered upon the prophet (pbuh) and saw him praying on a straw mat and he would prostrate on it.”
4- Maymunah (the wife of the prophet) narrates: “Rasulullah was praying with me next to him such that my clothing would come in contact with his when he would prostrate, and he would pray on a straw mat.”
There are many hadiths in this regard; we will leave it at the ones we mentioned here to keep it short.
c) Hadiths that say it is permissible to prostrate on other than earth in extenuating circumstances:
Here we will only mention the hadith of Anas bin Malik. Anas says: “We would pray with the prophet (pbuh). Whenever one of us couldn’t put his forehead on the ground because of the heat, he would spread his shirt on the ground and prostrate on it.”
This hadith has been mentioned in different Sunnis sources, most notably in Sahih Bukhari and Sahih Muslim, with different wordings.
Every researcher, through observing and examining these hadiths, will come to the clear conclusion that all of these hadiths revolve around the fact that prostration must be done on earth, then on what grows from the earth, other than what is eaten or worn from it, and in certain circumstances, on one’s shirt.
It is based on these hadiths that the scholars and jurists of the school of the Ahlul-Bayt, following the hadiths of the Ahlul-Bayt, say: “It is mandatory that the place of prostration [where one puts his forehead] to be of earth or anything that grows from it, which isn't of the things normally eaten or worn.”
As for why we (the Shia) dry some soil and clay and make it in the shape of small tablets and prostrate on it, there are reasons for it that we will mention some of:
1- It is a way of ascertaining that the place we are putting our foreheads for prostration is tahir, because as you know, one of the conditions of sujud in prayer, is for the place you are putting your forehead to be tahir. Also, it is a way of ascertaining that the place we are putting our forehead is mubah, meaning that its use is permissible (i.e., it is not usurped).
2- Nowadays, masjids and our homes where we pray, are floored with rugs and the like, and there is no soil or earth to prostrate on, therefore, this is a convenient way of observing the condition of prostrating on soil.
The reasoning behind prostrating on the soil of the grave of Imam Husayn (as)
As for why the Shia prostrate on the soil of the grave of Imam Husayn, one must say:
1- Among the Shia scholars, not even one can be found who has said it is mandatory to prostrate on such soil. What they all say is that any soil that is tahir and is mubah can be used for prostration in prayer, as was mentioned above. What they do say is that prostration on the soil of Imam Husayn (as) is mustahabb and recommended.
2- Prostrating on the soil of Imam Husayn (as) is an instance and example of prostrating on soil, and prostrating on soil is something that all Muslims agree and have a consensus on. Thus, there is no reason to exclude the soil of Imam Husayn’s (as) soil from all other soils in general, leaving no room for any questioning on why the Shia prostrate on the soil of Imam Husayn (as).
3- The Ahlul-Bayt would emphasize greatly on prostrating on the soil of Imam Husayn (as) and Imam Sajjad (as) was the first imam to do so. All of the imams would prostrate on the soil of Imam Husayn (as) and would stress on its recommendation. Imam Sadiq (as) says: “Prostrating on the soil of the grave of Imam Husayn (as) removes the ‘Seven Veils’.”
4- Many different reasons suggest that prostrating on the soil of Imam Husayn (as) has preference. Scholars are well aware of these reasons:
a) Beliefs: On the dawn of the day of Ashura, Umar bin Sa’d prayed fajr prayer with his army, but in the afternoon of that same day, he had Imam Husayn (as) martyred. By prostrating on the soil of Imam Husayn (as), the Shia proclaim that a dead prayer is worthless and without spirit, just like the prayer of Umar bin Sa’d and his head, Yazid. They show that their prayer is like that of Imam Husayn (as) and his father and grandfather. This is what consolidates the concept of wilayah for the followers of the imam.
This is why the imams would emphasize on prostrating on such soil. Prostration on it signified submission and humility before Allah (swt), through following His chosen ones.
b) Historical teachings: Throughout history, there have been those who have tried to bury the truth and teachings of Ghadir, about Imam Ali (as) being imam and successor to the prophet, and also the truths and incidents of Ashura; the soil of Imam Husayn (as) is a living proof of the atrocities of the Umayyids on Ashura. This keeps Ashura alive throughout the ages, despite the painstaking efforts of the transgressors to put out the light of these important occasions.
The imams and Ahlul-Bayt instilled Ashura in the hearts and minds of their followers through eulogies, weeping and tears, ziyarat, etc., making a connection between them and Ashura. This fact also reiterates the importance of prostration on the soil of Imam Husayn (as).
c) Teachings of jihad and martyrdom: The soil of Imam Husayn (as) is one of those things that can spark revolution and jihad in most of the Muslims, something that the Muslim nation is in need of, especially in the world we live in today, where the Islamic nation is being attacked from every angle. Using the soil of Imam Husayn (as) isn't merely use of any other normal spiritless soil, it is rather our connection with a great power and the concept of jihad and martyrdom.
In addition to all of this, the soil of Imam Husayn (as) encompasses moral, political, religious, etc. teachings, all of which can be found in detailed books on this subject.
In conclusion, we see it befitting to ask: What was the sin of the Shia and what had they done wrong? Was it other than the fact that they relied on the teachings of the prophet (pbuh) and followed his way and took him as their role model in his sure and proven actions and demeanor, practicing precaution in doubtful acts of Islamic law attributed to him, such as prostrating on clothing and rugs and the like in cases where there were no excusing circumstances?
There are many hadiths that point to the reasoning behind the impermissibility of prostrating on edible and wearable things. One of those hadiths is the following:
Hisham says that he said to Imam Sadiq (as): “Please inform us of the things prostration is permissible on and those that can't be prostrated on.” The imam (as) replied: “Prostration is impermissible except on earth and whatever grows from it, except those things of them that are edible and wearable.”
Hisham says: “I said: May I be your sacrifice! What is the reason for this?” The imam (as) answered: “Because prostration is for [expressing] humility before Allah, so it isn't appropriate for it to be edible or wearable, because the people are the slaves of the edible and wearable, while the one prostrating is [supposed to be] worshipping and serving Allah in his prostration, so it isn't appropriate for his forehead to be on the object of worship of the slaves of this world and those who have fallen for this world. Prostration on soil is better, because such a prostration is more signifying and expressive of one’s humility and servitude for Allah (swt).”
 Ibn Habban, Sahihah, vol. 1, pg. 264.
 Muslim, Sahih, vol. 3, pg. 312; Ibn Majah, Sunan, vol. 2, pg. 360.
 For further information, see: Al-Fiqh ala al-Madhahib al-Arba’ah, Al-Jaziri, Abd al-Rahman.
 Allamah Amini, Al-Sujud ala al-Turbah al-Husayniyah, pg. 13.
 Sahih al-Bukhari, vol. 1, pg. 113; Sahih Muslim, vol. 2, pg. 64; Sahih Nisa’i, vol. 2, pg. 32; Sahih Abi Dawud, vol. 2, pg. 114; Al-Sunan al-Kubra, vol. 2, pp. 433 and 435.
 Sahih al-Nisa’i, vol. 2, pg. 37.
 In his Mustadrak, Hakim has narrated this hadith and Dhahabi has corrected it, vol. 3, pg. 473.
 Sahih al-Bukhari, vol. 1, pp. 2, 198, 163, 253, 256, 258, 259; Sunan Abi Dawud, vol. 1, pp. 143-144; Al-Sunan al-Kubra, vol. 2, pg. 106.
 Al-Sunan al-Kubra, vol. 2, pg. 106.
 Sunan Abu Dawud, vol. 1, pg. 75; Al-Sunan al-Kubra, vol. 2, pg. 440.
 Al-Sunan al-Kubra, vol. 2, pg. 105.
 For further information on the hadiths in this regard, see: “ما هی فلسفة السجود علی التربة”, Question 508 of Arabic section (website: 554).
 Musnad Ahmad Hanbal, vol. 1, pg. 321; Al-Sunan al-Kubra, vol. 2, pg. 105.
 Bukhari, Sahih, vol. 1, pg. 101; Sahih Nisa’i, vol. 2, pg. 57.
 Ibn Majah, Sunan , vol. 1, pg. 255.
 Sahih Nisa’i, vol. 2, pg. 57.
 Tirmidi, Sahih, vol. 2, pg. 126.
 Sahih Muslim, vol. 2, pp. 62 and 126.
 Bukhari, Sahih, vol. 1, pg. 101; Muslim, Sahih, vol. 2, pg. 128.
 Bukhari, Sahih, vol. 1, pg. 101; Muslim, Sahih, vol. 2, pg. 109; Ibn Majah, Al-Sunan, vol. 1, pg. 321; Abu Dawud, Al-Sunan, vol. 1, pg. 106.
 See: Al-Urwah al-Wuthqa, vol. 1, chapter of prostration, what is permissible to prostrate on.
 See: Tahrir al-Wasilah, Imam Khomeini, vol. 1, chapter of what is prostration is correct on.
 Wasa’il al-Shia, vol. 6, pg. 23.
 Abd al-Mun’im Hasan, Bi Nuri Fatimah Ihtadayt, pp. 203-204; quoted from Al-Farifi, Seyed Abdullah, Al-Tasahyyu’, pg. 206.
 Man La Yahduruhu al-Faqih, vol. 1, pg. 273.