An adherent or the follower of Islam is called a Muslim. The word "Muslim" also means one who submits to the will of Allah سبحانه و تعالىThe first principle of Islam is known as the Shahadah (Testimony of Faith), and is as follows: "There is no one worthy of worship except Allah سبحانه و تعالى(God) and Prophet Muhammad ﷺ is the Final Apostle (Messenger) of Allah سبحانه و تعالى.” In a broader sense, anyone who willingly submits to the will of God is a Muslim. Thus, all the prophets preceding Prophet Muhammad ﷺ, are considered Muslims because they all have submitted their will to almighty God(Allah). 
A true Muslim is the one who has disciplined his life in accordance with the instructions conveyed by Allah سبحانه و تعالىthrough His Messengers ﷺ. A person becomes a Muslim not by birth alone, but by his Faith and Deeds. The word MUSLIM is used in Qur’an in several places, Allah سبحانه و تعالىsays in the Qur’an "Abraham was neither a Jew nor a Christian; but an upright Muslim (i.e. one who submitted to Allah سبحانه و تعالى)." Qur’an.Surah Al-Imran 3:67
And the Muslim word comes in several places of Qur’an.Surah Baqrah 2:128, 132, 133, A’le-Imran 3:52, 64,102, An’am 6:163 and Surah Fusilat 41:33 and in various other places. 
According to 'Abdullah bin 'Amr رضي الله عنه: "I heard the Messenger of Allah ﷺsaid: "The Muslim is the one from whose tongue and hand the Muslims are safe, and the Muhajir is the one who forsakes (Hajara) that which Allah سبحانه و تعالىhas forbidden to him." Sahih Al-Bhukari Vol. 6: 4999 
Everything that submits to the law of Almighty God is a Muslim
He who surrenders to Almighty God and obeys the laws of Almighty is called as MUSLIM IN ARABIC.
- So when the child comes out of mother’s womb at the time when God has ordered – what is it? It is Muslim.
- When the Earth goes around in its orbit – what is it? It is Muslim.
- When the Sun goes around in its orbit – what is it? It is Muslim.
- When the Moon goes around the Earth – what is it? It is Muslim.
- The Law of Gravity – what is it? It is Muslim.
- Therefore, everything that submits to Almighty God “Allah سبحانه و تعالى” is a Muslim. Therefore, when we willingly obey Allah سبحانه و تعالىthen we are Muslims.
3 key elements for Muslim
A Muslim life is characterized by three key elements:
1. Eeman or Iman, which is faith in Allah, angels, scriptures, messengers, the Last Day, and divine decree;
2. Islam or the 5 pillars: the testification of faith, regular prayer, mandatory alms, Ramadan fasting, and hajj.
3. Ihsan, or spiritual excellence in the above and your dealings with fellow humans
Some of the Muslims qualities which Allah سبحانه و تعالى, the almighty loves the most
"Say (O Muhammad ﷺto mankind): "If you (really) love Allah سبحانه و تعالى, then follow me (i.e. accept Islamic monotheism, follow the Qur’an and the Sunnah), Allah سبحانه و تعالىwill love you and forgive you your sins. And Allah سبحانه و تعالىis Oft-Forgiving, Most Merciful." Qur’an.Surah Al-Imran 3:31
"And Allah loves as-Sabirun (the patient)." Qur’an.Surah A’le-Imran 3:146.
Justice and Dealing with Equity
"Be just: that is nearer to piety; and fear Allah سبحانه و تعالى."Qur’an.Surah Al-Maida 5:8.
Putting Trust in Allah
"Certainly, Allah loves those who put their trust (in Him)." Qur’an.Surah A’le-Imran 3:159.
Perfection of One's Work
The Messenger ﷺsaid: "Allah سبحانه و تعالىloves that if one does a job he perfects it."
Abu Ya ‘la Dailami رحمت اللهand Ibn Asakir رحمت اللهnarrated: Abu Hurairah رضي الله عنهand Anas Ibn Malik رضي الله عنهsaid: Allah's Messenger ﷺsaid: "Allah سبحانه و تعالىloves rescuing the one who needs rescue."
Being Kind and Gentle to Others
Baihaqani رحمت اللهnarrated: Allah's Messenger ﷺsaid: "Allah سبحانه و تعالىis kind and gentle (to others)."
"Aisha رضي الله عنهnarrated: The Messenger of Allah ﷺsaid: "Allah سبحانه و تعالىis kind and lenient and likes that one should be kind and lenient in all matters" Sahih Al Bhukari Vol 9:61
"Truly, Allah سبحانه و تعالىloves those who turn unto him in repentance." Qur’an.Surah Al-Baqra 2:222.
"Verily, then Allah سبحانه و تعالىloves those who are al-Muttaqun (the pious)." Qur’an.Surah Al'e Imran 3:76 and Surah Taubah 9:4.
"Truly, Allah سبحانه و تعالىloves Al-Muhsinun (the good-doers)." Qur’an.Surah Al-Baqra 2:195.
"And Allah سبحانه و تعالىloves those who make themselves clean and pure [ i.e. who clean their private parts with dust (which has the properties of soap) and water from urine and stools, after answering the call of nature]." Qur’an.Surah At-Taubah 9:108.
Humility of the Rich
Sa'd Ibn Abi Waqqas رضي الله عنهsaid: Allah's Messenger ﷺsaid: "Allah سبحانه و تعالىloves the believer who is pious and rich, but does not show off." Bulugh al Marham 1517
Belief and Work
Al-Tabarani narrated: Allah's Messenger ﷺsaid: "Allah سبحانه و تعالىloves the slave who believes and acquires a career (or work)."
Reflection of Allah's Grace
Al-Tirmidhi narrated: Allah's Messenger ﷺsaid: "Allah سبحانه و تعالىloves from amongst his slaves, the one who has a sense of zeal or honor."
Al-Hakim narrated: The Messenger of Allah ﷺsaid: "Allah سبحانه و تعالىis All-Generous and He loves generosity in sale, purchase and judgment."
The Messenger of Allah ﷺsaid: " Allah سبحانه و تعالىloves the slave-believer who is poor but virtuous enough to refrain from begging though he has many children." (Muslim and Ahmed)
Al-Tabarani narrated: the Messenger of Allah ﷺsaid: "Allah سبحانه و تعالىloves lofty matters and superiority and hates inferior matters."
Allah's Messenger ﷺsaid: "Allah سبحانه و تعالىloves that you be just toward your children even when kissing them."
Muslim narrated: Allah's Messenger ﷺsaid: "The strong believer is better and more loved by Allah سبحانه و تعالىthan the weak one, but they are both good."
Love for the Sake of Allah سبحانه و تعالى
Al-Tabarani, Ibn Ya'la, Ibn Hibban and Al-Hakim narrated: Allah's Messenger ﷺsaid: "If two men love each other for the sake of Allah سبحانه و تعالى, the stronger in love to his brother will be more loved by Allah سبحانه و تعالى."
Ibn Iday رحمت اللهnarrated: Allah's Messenger ﷺsaid: "Allah سبحانه و تعالىis All-Forgiving and He loves forgiveness."
Continuous Performance of Righteous Deeds
Bukhari and Muslim narrated: Allah's Messenger ﷺsaid: "The best loved deeds to Allah سبحانه و تعالىare the ones that are continuous even if they are not very many."
Loving and Visiting Believers
Malik narrated: Allah's Messenger ﷺsaid: "Allah سبحانه و تعالىsaid: My love is due to those who meet for My sake, visit one another and make any effort for My pleasure."
Exhortation and Advising
Abdullah رحمت الله, the son of Imam Ahmed رحمت اللهnarrated: It was said: Allah's Messenger ﷺsaid: "The best loved slaves to Allah سبحانه و تعالىare those who exhort their slaves."
Love of Virtuous Deeds
Ibn Abi Al-Dunya رحمت اللهnarrated: Allah's Messenger ﷺsaid: "The best loved slaves to Allah سبحانه و تعالىare those who are made to love virtue and loving virtuous deeds is made lovely to them."
Good Manners and Conduct
Al-Tirmidhi narrated: Allah's Messenger ﷺsaid: "The best loved by me and the nearest to me on the seats on the Day of Resurrection are those who have the best manners and conduct amongst you, who are intimate, are on good terms with others and are humble, and the most hated by me and who will be on the furthest seats from me are those who are talkative and arrogant."
Love of Allah سبحانه و تعالىis the basis of worship that should be directed to Him alone. Any other love should be for His sake too. The real love of Allah سبحانه و تعالىis to do whatever He ordained and to abandon whatever He forbade, in addition to following the Prophet's ﷺSunnah.
Whoever obeys someone or something other than Allah سبحانه و تعالىand His Messenger, or follows any saying other than theirs, or fears other than Allah سبحانه و تعالىor seeks the pleasure of other than Allah سبحانه و تعالى, or puts his trust in other than Him, does not love Allah سبحانه و تعالى, nor does he love His Messenger ﷺ. Muslims should also love one another and wish the best for one another.
Allah's Messenger ﷺsaid:"One will not be a true believer unless he loves for his brother what he loves for himself." (Bukhari, Muslim, Tirmidhi Vol 4:2515Nasa'I Vol 6:5020, Ahmad and Ibn Majah Vol 1:66) 
The Muslim personality is balanced. He pays due attention to his body’s needs and his outward appearance, without letting it distract him from nurturing his inner characteristics, as befits man whom God has honored and made His angels prostrate to him, and subjugated for his benefit all that is in the heaven and earth. The Muslim is also concerned with that which will form sound intellectual development and ways of thinking, so that he understands the nature and essence of things. He does not forget that man is not only composed of body and mind, but he also possesses a soul and a spirit, and feels a longing for higher things that makes him rise above this materialistic life and ascend the heights of goodness, virtue and light. Therefore, he pays as much attention to his spiritual development as he does to his physical and intellectual development, in a precisely balanced fashion, which does not concentrate on one aspect to the disadvantage of others.
With his parents, he is an example of sincere filial piety, good treatment, infinite compassion, politeness and deep gratitude.
With his wife, he is an example of good and kind treatment, intelligent handling, deep understanding and proper fulfillment of his responsibilities and duties.
With his children, he is a parent who understands his great responsibility towards them. Although he floods them with love and compassion, he pays attention to things that may affect their Islamic upbringing.
With his relatives, he maintains the ties of kinship and knows his duties toward them. He understands the high status given to relatives in Islam, which makes him remain in touch with them regardless of the circumstances.
With his neighbors, the true Muslim is an example of good treatment and consideration of others’ feelings and sensitivities. He puts up with mistreatment and turns a blind eye to his neighbor’s faults while avoiding committing any such errors himself. He always adopts the Islamic attitude, whereby treating neighbors well was made a basic principle of Islam. His relationship with his brothers and friends is the best and purest of relationships, for it is based on love for the sake of God. This pure, sincere, brotherly love derives its purity from the guidance of the Quran and Sunnah.
Summary of Muslims
We can thus summarize the teachings of Islam about the Muslim character concisely in the following way:
- A Muslim is truthful, not dishonest
- He is humble, not arrogant
- He is moderate, not an extremist
- He is honest, not corrupt
- He is reserved, not garrulous
- He is soft-spoken, not boastful
- He is loving and solicitous to others, not unmindful of them
- He is considerate and compassionate, not harsh
- He is polite and helpful, not insulting and disrespectful to people
- He is generous and charitable, not selfish and miserly
- He is refined and gentle in speech, not prone to swearing or cursing
- He is cheerful and generous, not bitter and resentful
- He is grateful for what he has, not ungrateful
- He is cheerful and pleasant, not irritable and gloomy
- He is chaste and pure, not lustful
- He is alert, not absent-minded
- He is dignified and decent, not graceless
- He is sincere and straightforward, not hypocritical
- He is optimistic and hopeful, not cynical or pessimistic
- He is confident and deep in faith, not doubtful and wavering
- He is spiritually oriented, not materialistic
- He always has faith in God’s mercy, not losing heart or becoming desperate
- He is diligent and vigilant, not negligent to his duties
- He is thankful to God and constantly prays to Him, not forgetful of His innumerable blessings 
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