As explained in the first part of the topic, Islam has spread much more quickly compared to other religions all over the world. The traits of Prophet Muhammad (PBUH&HP) were introduced as one of the reasons. Here, the effect of the scientific and social interactions with the rest of the world throughout the Islam's history is discussed. 

 As an introduction, it is good to know that Islam has adopted two types of regulations; confirmed rules and established ones. The Islamic approach regarding the confirmed rules -the regulations which existed before and were conserved or revised if needed- is one of the keys to the development and permanence of Islam. And, this will be the focus of this article.   

Saying Yes to the Good Costumes throughout Islam's History

The Islamic approach to the habits and rules that were common in the pre-Islamic era was that it neither opposed them totally nor accepted them entirely. In some cases, Islam has affirmed and preserved some rules. That was when those rules or customs were not in contradiction to the social order and the living facilities of humans or in case of the righteous customs and traditions that existed before the emergence of Islam; e.g., some of the rules on making contracts. 

However, some of the useful regulations required to be revised and this was accomplished by adding some conditions. On the contrary, some customs and routines were opposed and removed due to the bugs and disadvantages or because they were manipulated or misused for personal benefits; e.g., usury (Riba) [1].

The rules conserved by Islam, such as those about the ownership and property, are called confirmed rules. On the other hand, the rules instituted by the Islamic jurisprudence which never existed before are called established rules [1]. This demonstrates that Islam has always been in constant interaction with the world, and the positive aspects of human societies are considered. Hence, the message of Islam and its framework have not been far from what people are familiar. This consequently has made it easier to accept Islam.

Seeking knowledge; A Way to Spread Islam

Islam has urged everyone to seek knowledge. The first verse of the Quran revealed to Prophet Muhammad (PBUH&HP) enjoined reading which is the key to knowledge: “Read in the Name of your Lord who created” (96:1). Literacy and having knowledge are so important in Islam that Quran equals illiteracy to being in darkness. According to Prophet Muhammad (PBUH&HP), seeking knowledge is obligatory (Wajib) for every Muslim and God loves those who seek knowledge [2].

Learning and seeking knowledge have been emphasized such that Muslims have been encouraged even to travel in order to learn things. Imam Ali (AS) recommended traveling to acquire privilege and named gaining knowledge as one of the achievements of traveling [3]. Prophet Muhammad (PBUH) advised seeking knowledge even if for that purpose one should go to the lands far away [4].

The Holy Quran also addresses the believers as those who are not affected by the wrong behaviors of others since they have been guided. So, the believers can peacefully learn from the positive aspects of others. Another proof of the attention paid to knowledge in Islam is that Muslims used to release the prisoners of wars who taught literacy to a certain number of Muslims. All these emphases and recommendations have urged Muslims to travel to gain knowledge. As a result, Muslims who traveled to other places and countries were practically the messengers of Islam there, which, in consequence, accelerated the spread of Islam.

Continuous interaction with the world During Islam's History 

The actual advances all over the world are the outcomes of the efforts that various nations and civilizations have made in the course of time, among which are the Islamic civilizations [6]. Muslims in different countries, like Spain and Italy, have always been in interaction with other people; therefore, they could transfer the Islamic civilization and culture to others and also receive from them. As an instance, in the battle of the Trench (Khandaq), Salman Farsi proposed to dig a trench around Medina.

This was a tested strategy in Persia, and Prophet Muhammad (PBUH&HP) accepted it. Many of the important Arabic resources and books were translated into European languages, some of which were later on taught and used as references in scientific centers in non-Muslim countries. The bonds between Muslims and Christians through marriage [i] and social relationships were of other means to expose non-Muslims to Islam [7]. All these factors have helped the quick spread of Islam.

From what has been discussed, we can see that the Islamic approach of making regulations under the form of confirmed rules, the encouragement to obtain knowledge and literacy, and cultural exchanges with the rest of the world played significant roles in attracting many savants and people to the religion of Islam.    

Notes:
[i] This kind of marriage named Interreligious marriage is permitted in Islam under the certain conditions. 

References:

1. spreading Islam
2. “Misbah al-Shariah”, p. 13.
3. M. Nuri, “Mustadrak al Wasail”, vol. 18, p. 115.
4. “Misbah al-Shariah”.
5. “Ghurar al-Hikam wa Durar al-Kalim”, p. 46, T. 188.
6. history of Islam
7. A. Velayati, “Dynamism of Islamic and Iranian Culture and Civilization”, vol. 1. 

Ramadan is the ninth month of the Islamic calendar, observed by Muslims worldwide as a month of fasting, prayer, reflection and community. In this holy month Muslims fast from the food, drink, smoking, and sexual activity, and other specific activities drawn by Islam between dawn to nightfall until when the evening adhan is sounded in order to practice abstaining. There is definitely a higher purpose beyond not eating or drinking behind fasting. Fasting is one of the Principles of Islam, a religious duty commanded by Allah. Muslims who obey such commands or duties are said to receive thawab* each time for each good deed and receive redemption in the afterlife. Today we are going to discuss the real philosophy behind this Principles but at first, let us see some of the Quran verses pointing to fasting and its place in Islam. 

Almighty Allah says: 

O you who have believed, decreed upon you is fasting as it was decreed upon those before you that you may become righteous – 
(The Holy Quran 2:183) 

Also:

The month of Ramadhan [is that] in which was revealed the Qur'an, a guidance for the people and clear proofs of guidance and criterion
(The Holy Quran 2:185)

The high purpose of Fasting

This principle is often emphasized in the principles of Islamic jurisprudence “The basis for the formation of all religious and divine rules is the interests and corruptions that philosophy is its cause”. 

The second surah of The Quran (Al-Baqarah) clearly telling us the purpose of the act of fasting, talks about Divine bowing (verse 185), thanksgiving (verse 185), Benefiting from divine help (verses 45 and 153), benefiting from Allah (verse 184), attaining piety (Verse 183) and victory and success in deeds (verses 45 and 153) are among the wisdom and goals of fasting. We will discuss them deeply now:

1. The test of sincerity

Fasting has other benefits and effects, the most important one is identifying the sincere; Because fasting means abstaining from drinking and eating and sexual pleasures as well as other prohibitions, it is very difficult for many people who cannot wash their hearts of material pleasures and are only humble and submissive who give up by divine command. Therefore, it can be said that fasting is one of the most important divine tests through which sincerity can be recognized. Imam Ali (AS) says about this function of fasting: Allah made fasting obligatory in order to test the sincerity of the people. (1) Also, Lady Fatemeh (AS) says about the role of fasting insincerity: Allah has made fasting obligatory in order to establish sincerity. (2)

2. Fasting and empathy with others

Other functions of fasting include the element of empathy; Because the fasting person understands the difficult conditions of others by fasting, and because of the suffering he suffers during the fast, he feels the suffering of the poor deeply now. Creating similar conditions and assimilating the living space with the lives of the poor, in the most important dimension, namely the lack of food and drink and other pleasures, causes a feeling of sympathy and provides the ground for financial benevolence and charity. Some rich people, for various reasons, including illness or intentionally not fasting, have to pay atonement, so one of the purposes of fasting is to reach a part of the wealth and property of the rich to the poor so that at least the life of the poor is provided and the level of class distance becomes slightly lower.

we can also refer to this wisdom that Imam Sadigh (AS) has stated about the obligation of fasting: Allah has made fasting obligatory so that the rich and the poor become equal (3) Imam Reza (AS) also says about this matter: People are commanded to fast in order to understand the pain of hunger and thirst, and through it to find the poverty and misery of the Hereafter. (4)

3. Fasting, the Zakat (charity) of body

Another wisdom mentioned in the narrations for fasting is zakat of the body. In the sense that zakat is for everything; That is, just as it is zakat for property, which by paying for it provides the ground for proper growth and development of the body. Prophet Mohammad (PBUH&HP) said: Zakat is for everything and zakat on the bodies is fasting. (5) Also, our dear Prophet (PBUH&HP) said: Fast to stay healthy (6)

Medical research has proven today that fasting has a very effective role in eliminating diseases, especially cancer; this is because the lack of nutrients in the body has the first effect on cancer cells and dries out their roots. Therefore, in order to have a healthy body and all the organs of the body to work properly, we must accept fasting as a treatment and use it for the proper development of our body.

4. Fasting is a kind of Jihad

In the teachings of Islam, Jihad, especially its military one, has been set as a standard for other tasks due to its difficulty to achieve. Therefore, matters such as gaining halal, marrying well, and the like are considered and measured as jihad. Fasting is a difficult and arduous task because it is even permissible to step on carnal pleasures. Fighting against carnal desires and confronting erotic issues is one of the most important jihads known as the Great Jihad; and it is more difficult to fast in the heat of summer and under the sun and with work and labor. Such a fast is one of the best examples of deeds from the ideals of Prophet (PBUH&HP) that he said: Fasting in the heat is jihad. (7)

Imam Sadegh (AS) also says about fasting in extreme heat: Whoever fasts for Allah on a very hot day and becomes thirsty, Allah will appoint a thousand angels to touch his face and give him the good news until he breaks his fast. (8)

The best fast

Achieving true fasting means that not just a person's body and tongue fasting, but also his heart and mind are fasting. Imam Ali (AS) says in expressing the best types of fasts: The fast of the heart is better than the fast of the tongue, and the fast of the tongue is better than the fast of the belly (9). So, in the real fast, all the organs of a person must be fasting from sin and mistakes. It is also narrated from Lady Fatima (PBUH) that: What is the use of fasting for a fasting person who has not preserved his tongue, ears, eyes, and joints? ** (10) 

Conclusion

There is no point in Islam that hasn’t been checked by wisdom higher than human ones. If there are acts in Islam that are hard or pointless in our sight, that means we can’t see their higher purpose. Islam is always fresh and never gets old like other religions and it seeks human redemption so follow its orders to find yourself in the righteous path 

References:

1. Nahj al-Balagha (verse 252)
2. Bihar al-Anwar (96th volume – page 368)
3. Man La Yahduruhu al-Faqih (second volume – page 43)
4. Wasa'il al-Shia (4th volume – page 4)
5. Al-Kafi (4th volume – page 62)
6. Bihar al-Anwar (96th volume – page 255)
7. Bihar al-Anwar (96th volume – page 257)
8. Al-Kafi (4th volume – page 64)
9. Exalted Aphorisms and Pearls of Speech (first volume – page 417)
10. Bihar al-Anwar (93th volume – page 295)

* Thawab means punishment and has been used in both good and evil deeds of the human, and of course it is often used in good deeds.
**Lady Fatima (AS) has made a Denial interrogation in this narration of hers that it makes it more understandable