Indeed, Arabic is part of a Muslim’s identity which he should preserve and do his best to develop. This is because Arabic helps a Muslim to protect his Muslim identity from getting dissolved in majority non-Muslim communities. That is why Muslim minorities in those communities are advised to do their best to make Arabic their first language. But in the meantime, they should not stop learning the languages of the countries of their residence to be able to administer their day-to-day life affairs.
In this regard, Sheikh `Abd Ar-Rahman `Abd Al-Khaliq, Head of the Islamic Heritage Committee in Kuwait, states the following: One of the priorities of every Muslim, including Muslim minorities in the West, is to speak Arabic as their first language whatever language they learn during their childhood. This is because the Arabic tongue is strongly related to Islam and cannot be separated from it, as the true understanding and learning of Islam can hardly be achieved without learning Arabic—the language of the Glorious Qur’an, the Sunnah, and major references on Islam.
No matter how we try to translate the meanings of the Qur’an and Sunnah to any other language, such translations cannot serve as substitute to Arabic in understanding the miraculous nature of the Glorious Qur’an, the significance of the Prophetic Hadiths, and the facts about the Islamic sciences. Furthermore, learning Arabic came to mean belonging to the Muslim Ummah since Arabic is the symbol of Islam and the language of the Qur’an. Also, teaching the Muslim children Arabic will give them the keys to understanding the Qur’an, the Sunnah, the rulings of the Shari`ah, and will necessarily make of them an integral part of the Muslim Ummah. Being ignorant of Arabic will create a barrier between a person and Islamic sources. Moreover, young people who are content with learning a language other than Arabic will entirely restrict themselves only to the culture and arts of that language. In consequence, they will be brought up on its culture and arts. It is well known that the cultures and arts of all other languages – being written by non-Muslims – are not in line with the Islamic teachings.
to sum up, learning Arabic is the first step towards understanding and practicing Islam. It is a main pillar of being loyal to this religion and belonging to the Muslim nation. Therefore, Muslim minorities, regardless of their race or mother tongue, should resort to learning Arabic, giving it first priority even bef
ore their national language or the language of the country in which they reside.

Elaborating more on the above issue, Imam Ibn Taymiyah (may Allah shower his soul with mercy), adds:  Arabic is the symbol of Islam and the language of the Qur’an. Undoubtedly, it is a disliked act for Arabs to become accustomed to speaking a language other than Arabic to the extent of making that a habit in the whole city, with one’s family and household members, with one’s friends, in the marketplace, when addressing governmental representatives or authorities or scholars. This is because it is a form of imitating non-Arabs.
hence when the early Muslims went to live in Syria and Egypt, where the people spoke Byzantine Greek, and in Iraq and Khurasan, where the native language was Persian, and in the Maghrib (North Africa) where the people’s tongue was Berber, those Muslims didn’t relent efforts in teaching the people of those countries to speak Arabic, so that it became the prevalent language in those lands.
the best way is to get accustomed to speaking Arabic to make the young people learn it at their homes and schools. This will definitely help the symbol of Islam and Muslims prevail and will make it easier for Muslims to understand the Qur’an and Sunnah, and the words of the Salaf (early generation of Muslims), unlike a person who gets used to speaking one language, then wants to learn another, he will find it difficult.

Getting accustomed to using the Arabic language has a clear and strong effect on one’s thinking, behavior and religious commitment. It also has an effect on making one resemble the early generations of this Ummah, As-Sahabah (the Companions of the Prophet, peace and blessings be upon him,) and At-Tabi`un (the Successors).
Moreover, the Arabic language itself is part of Islam, so it’s obligatory for one to know it. If it is a duty to understand the Qur’an and Sunnah, and they cannot be understood without knowing Arabic, then the means needed to fulfill this duty is obligatory as well.
this is the meaning of the report narrated by Abu Bakr ibn Abi Shaybah who said: `Isa ibn Yunus told us from Thawr from `Umar ibn Yazid that `Umar wrote to Abu Musa Al-Ash`ari (may Allah be pleased with him), and said: ‘Learn the Sunnah and learn Arabic; learn the Qur’an in Arabic for it is Arabic.’
according to another Hadith narrated from `Umar (may Allah be pleased with him), he said: ‘Learn Arabic for it is part of your religion, and learn how the estate of the deceased should be divided (Fara’id) for it is part of your religion.’
this command of `Umar, to learn Arabic and Shari`ah combines the things that are needed, for religion consists of texts and practices. Understanding Arabic is the way to understanding the texts of Islam, and understanding the Sunnah is the way to understanding the Islamic practices…” (Iqtida’ As-Sirat Al-Mustaqim, vol. 2, p. 207)

In addition to the above, following are some tips for Muslim minorities to overcome the problem of language assimilation:
1. Muslims should strive– along with their families and children– to speak Arabic in their homes and gatherings. At home parents should set an example for their children and speak with them only in Arabic, and should not deliberately answer their children if they do not speak Arabic.
2. They should be keen to enroll their children in Arabic schools and academies wherever possible.
3. Muslim families should try to live close to one another, so that the neighborhood and the local environment will be Arabic-speaking.
4. Muslims should try to arrange Arabic-language courses as a means of obtaining Allah’s reward of and drawing closer to Him. Books, tapes and other modern educational means should be used for this purpose as well.
5. They should continually listen to recordings of the Qur’an, and tapes of Islamic lessons and lectures given in Arabic.