1. It has been narrated in the question from the holy Prophet (pbuh) that he said: “Cleanliness is half of faith”. Such a narration does not exist in hadith books or other Islamic sources.
2. What has been narrated from the Prophet in hadith books is "النظافة من الايمان" The hadith indicates that cleanliness is a part of faith or faith is the source of cleanliness. That is why a believer pays special attention to cleanliness.
3. Considering some traditions from the Holy Prophet (pbuh) who said: "بنى الدين على النظافة" (Religion is based on cleanliness) and also narrations from the infallible Imams about wudhu and purification such as “No prayer is valid without a purifying agent” perhaps, it can be said that cleanliness refers to purity. Not only prayer but also no act of worship is valid and accepted without purity and cleanliness (though the levels and types of cleanness from ritual impurity (Hadath) and physical impurity (Khabath) are different).
4. According to Islam, marriage which is the voluntary union for life of one man and one woman to the exclusion of all others is very important because it considers marriage as a means through which one can guard himself against sins, control his sexual desires, achieve peace and move on towards religious perfection. On the other hand, Islam is strongly opposed to monasticism and denounces those who adopt a monastic life considering monasticism as a barrier to perfection and prosperity. It is because of such an attitude that marriage is described as a means for safeguarding half of religion.
5. The term “half of religion” with regard to marriage is a term which underscores the importance of marriage for regular individuals or laity to persuade them to take action for marriage. Such interpretations are common.
6. Prayer, fasting, Hajj, Jihad, Wilayah etc. are among the terms used in religious texts quite often and with great emphasis. The emphases in the religious texts denoting their importance are no less than the emphases regarding marriage and cleanliness.
7. There are many narrations in which the elements of faith and Islam have been determined. For example, tawakkol (trusting in God) consigning one’s matters to God, being pleased with what God decrees, submission, kindness, truthfulness, loyalty, knowledge and humility, prayer, wilayah have been considered to be parts of faith. The relationship between “half of faith” and marriage or cleanliness is relative.
There is not such a narration from the Holy Prophet (pbuh) in our books and textual sources as to indicate that cleanliness is half of faith. What has been narrated from the Prophet in hadith books is "النظافة من الايمان" The hadith means that cleanliness is a part of faith or faith is the source of cleanliness. That is why a believer gives special attention to cleanliness. Since he is a believer, he is clean as well. It is for the same reason that cleanliness constitutes a part of faith. One cannot claim to be a true believer unless he pays attention to cleanliness. In any case, the word “half” does not exist in the narration, so your question in this regard is out of place.
It should be noted that cleanliness cannot be restricted to washing hands, face or clothes or house etc. rather, it has a more extensive meaning. If we study the instances of cleanliness, we will come to the conclusion that it includes even prayer, fasting etc. In other words, cleanliness refers to purify. If so, man’s thought and deeds would be fruitless without it. Therefore, not only can we say that “No prayer is valid without a purifying agent” but in fact no act of worship is valid and accepted without purification and cleanliness. If that is the case, faith without cleanliness will not be materialized.
In addition, wherever there is any mention of quantity in a narration, it refers to relative quantity. For example, if it is said that a person’s faith (iman) is completed with marriage, it means that when a married person is compared with an unmarried one, the married individual is more comfortable and is in a position to better perform his religious duties and obligations as he enjoys peace of mind and a tranquil heart. He is considered to have covered half of the way whereas an unmarried person struggles to safeguard his faith and himself against evil. It is for the same reason that marriage is considered an important factor in this regard.
The Holy Prophet of Islam (pbuh) has been narrated as having said: “Young men, adopt a spouse whoever from you can because marriage prevents you from looking at a non-mahram and makes you more modest…”
Islam emphasizes greatly on marriage considering it as a means for tranquility and peace of mind. It is a source of love and affection. When a person’s sexual instinct is controlled and his turbulent soul is balanced, he better understands the realities of life and is in a position to move faster towards his religion and prosperity. Truly, the comfort and peace and resulting from marriage are felt by those who have experienced the suffering of solitary and disorganized life and are aware of the worrisome and turbulent lives of youths.
On the other hand, Islam is strongly opposed to monasticism and denounces those who adopt a monastic life. The Holy Prophet of Islam (pbuh) said: "ليس فى اُمتّى رهبانية..." “There is no monasticism in my Ummah…” The Prophet (pbuh) never approved of people (like Uthman bin Maz’un) who avoided marriage and lived solitary lives. That was why the Holy Prophet (pbuh) said: God did not appoint me to indoctrinate monasticism, but He appointed me for the indoctrination of an easy and moderate religion. I go on fasting, I pray and I sleep with my wife. Anybody who loves my religion should behave as I do. Marriage is among my sunnah (customs)" It is only in this atmosphere and with this attitude that marriage is considered complementary to faith, and such interpretations have been passed on to us from the Infallibles – peace be upon them.
This is something customary. Meaning, if we want to tell someone about the importance of something, we tell him that if you do this and that, you have done half of the job or, for example, we tell him that half of the problem is because you do this and that. In fact, it is not true that if a thing is calculated precisely, it constitutes half of something or half of the problem. In fact, it means that it has a great role in solving or creating the problem.
Of course, it should not go without notice that it is possible that in some cases the reality of something may depend on two things and there might also be other things involved in its perfection. For example, if we had a narration stating that cleanliness is half of faith and marriage is also half of it, we could tell that the reality of faith is based on two pillars without which faith is not actualized. Prayer, fasting etc. have as much effect and role in religion as they complete and strengthen faith because faith is a matter of the heart and there are multiple factors involved in strengthening it. In addition, the importance and role of prayer in Islam and its impact in the individual and social life is not hidden to anyone. Prayer is the pillar of faith; it is remembrance of God. It helps a believer get proximity to God. It is the pillar of Islam, the criterion with which other acts of worship are assessed and evaluated. Whoever abandons prayers (either intentionally or because of negligence) is a Kafir (unbeliever).
Also, prayer, fasting, Hajj, Jihad, Wilayah etc. are among the terms used in religious texts quite often and with great emphasis. The emphases in the religious texts denoting their importance are no less than the emphases regarding marriage and cleanliness. Of course, as it was mentioned above cleanliness is not restricted to what is known in public. It has a vaster meaning which includes ritual impurity (Hadath), physical impurity (Khabath), purity of the heart from bad morality or from anything that is ungodly. It is for the same reason that in some sources, it has been narrated from the Holy Prophet (pbuh) that he said: "بنى الدين على النظافة" (Religion is based on cleanliness). Similar narrations have also been passed on from the infallible Imams about wudhu and purification.
It is necessary to note by referring to narrations regarding “faith”, “elements of faith”, “Islam” and “constituents of Islamic faith”, we come to learn that the basic elements of Islam and faith are not restricted to marriage and cleanliness. Here are a few narrations to go through.
1. Abu Hamzah narrates from Imam Baqir (a.s) that he said: “Islam has been founded and established on five things: Prayers, Zakat, Hajj, Sawm (Fasting) and Wilayah.”
2. When asked about definitions of iman (faith), Imam Sadiq (a.s) said: “Testifying the oneness of God and the Prophethood of Muhammad and acknowledging what has come down from God, offering the five obligatory prayers, paying zakat, fasting in the month of Ramadhan, pilgrimage of the House of God, loving those who love and being an enemy of those who are our enemies…”
Imam Sadiq (a.s) narrates from Imam Baqir (a.s), he from Ali (a.s) that he said: “Faith has four pillars, tawakkol (trusting in God), consigning one’s matters to God, being pleased with what God decrees and submission to God.”
Imam Sadiq (a.s) said: “Certainly Allah has divided faith into seven parts: goodness, honesty, conviction, contentedness, loyalty, knowledge and clemency.”
 "لاصلاة الاّ بطهور" Behar al-Anwar, vol.42, p. 245.
 Mustadrak al-Wasail, vol.2, p. 531, hadith 21.
 Behar al-Anwar, vol.70, pg. 115.
 Wasail al-Shi’ah, vol.14, p. 74
 Vide: Index, Prayer
 قال رسول اللَّه (ص): "الصلوة عماد الدين..." Behar al-Anwar, vol.82, p. 201; Also, the Commander of Faithful, Ali (a.s) said: "واللَّه اللَّه فى الصلوة فانها عمود دينكم" “By Allah, by Allah, prayer is the pillar of your religion”, Nahjul Balaghah, letter 47.
 Taha, 14.
 "الصلوة قربان كل تقى"، Nahjul Balaghah, Hikmat 136.
 عن ابى جعفر (ع) انه قال: "بُنى الاسلام على خمسة اشياء: الصلوة و..." Behar al-Anwar, vol.82, p. 234.
 قال رسول (ص): "الصلوة ميزان، من و فى استوفى" Al-Kafi, vol.3, p. 267, hadith 13; Al-Faqih, vol.1, p. 33, hadith 622; Wasail al-Shi’ah, vol.3, p. 22, chap. 8, hadith 8.
 Behar al-Anwar, vol.82, pg. 216 – 217.
 Mahajat al-Baidha, vol.1, p. 281.
 Vide: Wasail al-Shia’h, Kitab al-Taharah; Manners of Salat, Imam Khomeini, p. 94 – 55 etc.
 Vide: Behar al-Anwar, vol. 68, p. 329, also pp. 225 – 396.
 Ibid, p. 330, hadith 4.
 Ibid, p. 340, and 341, hadith 12.
 Ibid, vol.69, p. 159.