How did the classical scholars define Islam?

In a Nutshell: Most of the definitions of Islam introduced by the classical scholarship revolve around the linguistic definition of the term as it means the absolute surrender and submission to Allah alone and the complete obedience to all His precepts and ordinances, while not associating anything in worship with Him. Introduction Defining Islam is not an easy task as Islam is a comprehensive term signifying a wide range of meanings. In this answer, I will consider the definitions of Islam introduced by the classical Muslim scholars and provide an analysis of these definitions and explain why these definitions are not enough to provide a comprehensive view of Islam. Evidences Quran 1.    أَفَغَيْرَ دِينِ اللَّهِ يَبْغُونَ وَلَهُ أَسْلَمَ مَن فِي السَّمَاوَاتِ وَالْأَرْضِ طَوْعًا وَكَرْهًا وَإِلَيْهِ يُرْجَعُونَ - آل عمران 3/83 So is it other than the religion of Allah they desire, while to Him have submitted [all] those within the heavens and earth, willingly or by compulsion, and to Him they will be returned? (Qur'an 3:83) 2.    بَلَىٰ مَنْ أَسْلَمَ وَجْهَهُ لِلَّهِ وَهُوَ مُحْسِنٌ فَلَهُ أَجْرُهُ عِندَ رَبِّهِ وَلَا خَوْفٌ عَلَيْهِمْ وَلَا هُمْ يَحْزَنُونَ – البقرة 2/112 Yes [on the contrary], whoever submits his face in Islam to Allah while being a doer of good will have his reward with his Lord. And no fear will there be concerning them, nor will they grieve. (Qur'an 2:112) 3.    إِنَّ الدِّينَ عِندَ اللَّهِ الْإِسْلَامُ ۗ وَمَا اخْتَلَفَ الَّذِينَ أُوتُوا الْكِتَابَ إِلَّا مِن بَعْدِ مَا جَاءَهُمُ الْعِلْمُ بَغْيًا بَيْنَهُمْ ۗ وَمَن يَكْفُرْ بِآيَاتِ اللَّهِ فَإِنَّ اللَّهَ سَرِيعُ الْحِسَابِ – آل عمران 3/19 So if they argue with you, say, "I have submitted myself to Allah [in Islam], and [so have] those who follow me." And say to those who were given the Scripture and [to] the unlearned, "Have you submitted yourselves?" And if they submit [in Islam], they are rightly guided... (Qur'an 3:19) 4.    وَمَن يَرْغَبُ عَن مِّلَّةِ إِبْرَاهِيمَ إِلَّا مَن سَفِهَ نَفْسَهُ ۚ وَلَقَدِ اصْطَفَيْنَاهُ فِي الدُّنْيَا ۖ وَإِنَّهُ فِي الْآخِرَةِ لَمِنَ الصَّالِحِينَ -  إِذْ قَالَ لَهُ رَبُّهُ أَسْلِمْ ۖ قَالَ أَسْلَمْتُ لِرَبِّ الْعَالَمِينَ - وَوَصَّىٰ بِهَا إِبْرَاهِيمُ بَنِيهِ وَيَعْقُوبُ يَا بَنِيَّ إِنَّ اللَّهَ اصْطَفَىٰ لَكُمُ الدِّينَ فَلَا تَمُوتُنَّ إِلَّا وَأَنتُم مُّسْلِمُونَ – البقرة 2/130-132 When his Lord said to him, "Submit", he said "I have submitted [in Islam] to the Lord of the worlds. And Abraham instructed his sons [to do the same] and [so did] Jacob, [saying], "O my sons, indeed Allah has chosen for you this religion, so do not die except while you are Muslims." (Qur'an 2:130-132) 5.    فَلَمَّا أَسْلَمَا وَتَلَّهُ لِلْجَبِينِ - وَنَادَيْنَاهُ أَن يَا إِبْرَاهِيمُ  قَدْ صَدَّقْتَ الرُّؤْيَا ۚ إِنَّا كَذَٰلِكَ نَجْزِي الْمُحْسِنِينَ – الصافات 37/104-105 And when they had both submitted and he put him down upon his forehead, We called to him, "O Abraham, You have fulfilled the vision." Indeed, We thus reward the doers of good. (Qur'an 37 :104-105) 6.    فَلَا وَرَبِّكَ لَا يُؤْمِنُونَ حَتَّىٰ يُحَكِّمُوكَ فِيمَا شَجَرَ بَيْنَهُمْ ثُمَّ لَا يَجِدُوا فِي أَنفُسِهِمْ حَرَجًا مِّمَّا قَضَيْتَ وَيُسَلِّمُوا تَسْلِيمًا – النساء 4/65 But no, by your Lord, they will not [truly] believe until they make you, [O Muhammad], judge concerning that over which they dispute among themselves and then find within themselves no discomfort from what you have judged and submit in [full, willing] submission. (Qur'an 4:65) 7.    لَا شَرِيكَ لَهُ وَبِذَلِكَ أُمِرْتُ وَأَنَا أَوَّلُ الْمُسْلِمِينَ – الأنعام 6/163 No partner has He. And this I have been commanded, and I am the first [among you] of the Muslims."  (Qur'an 6:163) 8.    وَمَن يَبْتَغِ غَيْرَ الْإِسْلَامِ دِينًا فَلَن يُقْبَلَ مِنْهُ وَهُوَ فِي الْآخِرَةِ مِنَ الْخَاسِرِينَ – آل عمران 3/85 And whoever desires other than Islam as religion - never will it be accepted from him, and he, in the Hereafter, will be among the losers. (Qur'an 3:85) 9.    ضَرَبَ اللَّهُ مَثَلًا رَّجُلًا فِيهِ شُرَكَاءُ مُتَشَاكِسُونَ وَرَجُلًا سَلَمًا لِّرَجُلٍ هَلْ يَسْتَوِيَانِ مَثَلًا ۚ الْحَمْدُ لِلَّهِ ۚ بَلْ أَكْثَرُهُمْ لَا يَعْلَمُونَ – الزمر 29/39 Allah presents an example: a slave owned by quarreling partners and another belonging exclusively to one man - are they equal in comparison? Praise be to Allah! But most of them do not know. (Qur'an 29:39) Sunnah 1.    قَالَ يَا مُحَمَّدُ أَخْبِرْنِي عَنِ الإِسْلاَمِ قَالَ: ‏"أَنْ تَشْهَدَ أَنْ لاَ إِلَهَ إِلاَّ اللَّهُ وَأَنَّ مُحَمَّدًا رَسُولُ اللَّهِ وَتُقِيمَ الصَّلاَةَ وَتُؤْتِيَ الزَّكَاةَ وَتَصُومَ رَمَضَانَ وَتَحُجَّ الْبَيْتَ إِنِ اسْتَطَعْتَ إِلَيْهِ سَبِيلاً"‏.‏ قَالَ صَدَقْتَ... – مسلم 47/6 He (Jibreel) said: "O Muhammad, tell me about Islam." He said: "It is to bear witness that there is none worthy of worship except Allah and that Muhammad is the Messenger of Allah, to establish the Salah, to give Zakat, to fast Ramadan, and to perform Hajj to the House if you are able to bear the journey." He said: "You have spoken the truth." (Sahih al-Muslim 47:6) 2.    عَنْ أَبِي عَبْدِ الرَّحْمَنِ عَبْدِ اللَّهِ بْنِ عُمَرَ بْنِ الْخَطَّابِ رَضِيَ اللَّهُ عَنْهُمَا قَالَ: سَمِعْت رَسُولَ اللَّهِ صلى الله عليه و سلم يَقُولُ: " بُنِيَ الْإِسْلَامُ عَلَى خَمْسٍ: شَهَادَةِ أَنْ لَا إلَهَ إلَّا اللَّهُ وَأَنَّ مُحَمَّدًا رَسُولُ اللَّهِ، وَإِقَامِ الصَّلَاةِ، وَإِيتَاءِ الزَّكَاةِ، وَحَجِّ الْبَيْتِ، وَصَوْمِ رَمَضَانَ". رَوَاهُ الْبُخَارِيُّ وَ مُسْلِمٌ Islam has been built on five [pillars]: testifying there is no deity worthy of worship except Allah and Muhammad is the Messenger of Allah, establishing the salah (prayer), paying the zakat (obligatory charity), making the hajj (pilgrimage) to the House and fasting in Ramadan. (Sahih al-Bukhari and Muslim) 3.    عن جابر، يَقُولُ سَمِعْتُ النَّبِيَّ صلى الله عليه وسلم يَقُولُ ‏ "‏ الْمُسْلِمُ مَنْ سَلِمَ الْمُسْلِمُونَ مِنْ لِسَانِهِ وَيَدِهِ ‏"‏ ‏ A Muslim is he from whose hand and tongue the Muslims are safe. (Sahih al-Bukhari 81:73) Companions 1.   أَخْبَرَنَا يَزِيدُ بْنُ هَارُونَ، أَخْبَرَنَا بَقِيَّةُ، حَدَّثَنِي صَفْوَانُ بْنُ رُسْتُمَ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ مَيْسَرَةَ، عَنْ تَمِيمٍ الدَّارِيِّ، رَضِيَ اللهُ عَنْهُ، قَالَ: تَطَاوَلَ النَّاسُ فِي الْبِنَاءِ فِي زَمَنِ عُمَرَ رَضِيَ اللهُ عَنْهُ، فَقَالَ عُمَرُ: " يَا مَعْشَرَ الْعُرَيْبِ، الْأَرْضَ الْأَرْضَ، إِنَّهُ لَا إِسْلَامَ إِلَّا بِجَمَاعَةٍ، وَلَا جَمَاعَةَ إِلَّا بِإِمَارَةٍ، وَلَا إِمَارَةَ إِلَّا بِطَاعَةٍ، فَمَنْ سَوَّدَهُ قَوْمُهُ عَلَى الْفِقْهِ، كَانَ حَيَاةً لَهُ وَلَهُمْ، وَمَنْ سَوَّدَهُ قَوْمُهُ عَلَى غَيْرِ فِقْهٍ، كَانَ هَلَاكًا لَهُ وَلَهُمْ " There is no Islam except with jama'ah (body politic) and no jama'ah except with imarah (leadership), and no imarah except with ta'ah (obedience). (Darimi) Scholarly Views Arabic linguists defined Islam as linguistically meaning "surrender, obedience and subjection to Allah's commands and prohibitions". (Ibn Manzur, Lisan al-Arab, Vol. 12, p. 293; Fayumi, Al-Misbah al-Munir, p. 287) Classical scholars, however, introduced different technical definitions of Islam. The core is agreed upon in the above general definition, however subtle peripheral differences arose from their differing stances regarding: the relation between the concepts of Islam and Iman, whether Islam signifies the external surrender along with the internal, whether Islam and Iman are interchangeably synonymous with each other, and whether Islam can refer to the deen sent to all prophets or only the final deen. The following are some of the definitions of Islam cited by classical Muslim scholars, illustrating the similarity in a core understanding, that Islam is a collective institutionalised way of life for a qawm. 1. Islam: The Five Pillars of Islam Some scholars articulated extensional definitions through citing prominent aspects of Islam basing their definitions of Islam upon the hadiths 1 and 2 above. The Hanbali scholar Ibn Rajab is a well known example. فأما الإسلام ، فقد فسره النبى صلى الله عليه وسلم بأعمال الجوارح الظاهرة من القول والعمل ، وأول ذلك شهادة: أن لا إله إلا الله وأن محمدا رسول الله ، وهو عمل اللسان، ثم إقام الصلاة، وإيتاء الزكاة، وصوم رمضان، وحج البيت لمن استطاع إليه سبيلا. As regards to Islam, it is identified by the Prophet (saw) as referring to the external acts of the body, in words and deeds. The first one is the testimony: that there is no god but Allah and that Muhammad is the Messenger of Allah. This represents the work of the tongue. Then comes the performance of prayer, paying zakat, fasting Ramadan and making pilgrimage to the House if one is able to do so. (Ibn Rajab, Jami al-Ulum wa al-Hikam, p. 98) 2. Islam: Submission and Surrender to Allah Many scholars however depended on the linguistic definition, focusing on total and absolute surrender and submission to Allah. According to Abu Hanifah, Islam is defined as: الْإِسْلامُ هُوَ: التَّسْلِيمُ وَالْاِنْقِيادُ لِأوامِرِ اللهِ تَعَالَى فَمِنْ طَرِيقِ اللُّغَةِ فَرْقٌ بَيْنَ الْإِسْلامِ وَالْإيمَان وَلَكِنْ لَا يَكُونُ إيمَانُ بِلَا اسلامٍ وَلَا يُوجِدُ إِسْلامٌ بِلَا إيمَانٍ وَهُمَا كَالْظُّهْرِ مَعَ الْبَطْنِ وَالدِّينَ اِسْمُ وَاقِعٌ عَلَى الْإيمَانِ وَالْإِسْلامِ وَالشَّرَائِعِ كُلِهَا – أبو حنيفة في الفقه الأكبر 57 Islam is to surrender and to submit to the commands of Allah Most High. Hence, there is a literal difference between Iman and Islam. However, Iman (faith) does not exist without Islam nor Islam without Iman: they are as the back with the stomach. Deen is a noun that encompasses Iman, Islam, and all sacred laws. (Abu Hanifah, Al-Fiqh al-Akbar, p. 57) The sixth-century exegete Baghawi, defined Islam as:  والإسلام هو الدخول في السِّلم ، وهو الانقياد والطاعة. Islam means surrender and submission.  (Baghawi, Ma'alim al-Tanzil, Vol. 3, p. 18) Ibn Manzur defined Islam as: هو الاستسلام لله بالتوحيد والانقياد له بالطاعة والخلوص من الشرك كما عرّف بانه الاستسلام والانقياد ظاهرًا وباطنًا أو الاستسلام الظاهري فقط بمعنى الخضوع باللسان – ابن منظور في لسان العرب 5/185 Submission to Allah by worshipping Him alone, surrendering to Him by showing obedience to Him while not associating anything in worship with him. It is also defined as surrender and subjection to Allah internally and externally or defined as merely referring to the external obedience meaning surrender by the tongue. The sixth-century Hanbali scholar Ibn Abi Ya'la defined Islam as: الْإِسْلامُ فِي الشَّرَعِ عِبَارَةٌ عَنِ الشَهَادَتَيْن مَعَ التَّصْدِيقِ بِالْقَلْبِ – ابن أبي يعلي في الاعتقاد 24 Islam in shar'a (legislation) signifies the two shahadah (testimonies of faith), accompanied by tasdiq (assent) of the heart. (Ibn Abi Ya'la, Al-I'tiqad, p. 24) The eighth-century Hanafi jurist and theologian Taftazani, defined Islam as: الإسلام هو الخضوع والانقياد بمعنى قبول الأحكام والإذعان – التفتازاني في شرح العقائد النسفية 450 Islam means submission and surrender. In other words, it means accepting the rulings and showing obedience (Taftazani, Sharh al-Aqa'id al-Nasafiyyah, p. 450) The ninth-century scholar, Sharif Jurjani, defined Islam in his book al-Ta'rifat as: الإسلام هو الخضوع والانقياد لما أخبر به الرسول (صلى الله عليه وسلم)، وما وطأ في القلب واللسان فهو إيمان: أقول هذا مذهب الشافعي، وأما مذهب أبي حنيفة فلا فرق بينهما – الجرجاني في التعريفات 20 Islam means submission and surrender to what has been conveyed by the Messenger (saw). With regards to what lies at the heart, it is Imaan. This is the view of the Shafi'i madhab, whilst Abu Hanifah's madhab did not differentiate between both of them. (Jurjani, Al-Ta'rifat, p.20) According to Ibn Taymiyyah, Islam means: هُوَ الْاِسْتِسْلاَمُ لله لَا لِغَيْرِهِ، بِأَنْ تَكَوُّنَ الْعِبَادَةُ وَالطَّاعَةٌ لَهُ وَالذُّلٌ، وَهُوَ حَقِيقَةُ لَا إلَهٌ إلّا اللهَ – ابن تيمية في مجموع الفتاوى 5/ 239 It is the surrender to Allah alone by dedicating servitude, obedience and submission for His Sake. This the true meaning of "la ilaha ila Allah (There is no God but Allah)". (Ibn Taymiyyah, Majmu al-Fatawa, Vol. 5, p. 239) Ibn al-Qayyim, also defines Islam as: وَالْإِسْلامُ: هُوَ تَوْحِيدُ اللهِ، وَعِبَادَتهُ وَحْدَهُ لَا شَرِيكً لَهُ، وَالْإيمَانُ بِاللهِ وَبِرَسُولِهِ - صَلَّى اللهُ عَلَيه وَسَلَّمُ - وَاِتِّبَاعَهُ فِيمَا جَاءَ بِهِ فَمَا لَمْ يَأْتِ الْعَبْدُ بِهَذَا فَلَيْسَ بِمُسْلِمِ – ابن القيم في طريق الهجرتين/ 411 Islam is the Oneness of Allah, serving Him alone whilst not associating anything else with Him. It is also to believe in Allah and His Messenger (saw) and follow his traditions. If a servant does not fulfil these things, he is not a Muslim. (Ibn al-Qayyim, Tariq al-Hijratin, p. 411) Whilst ibn Kathir quotes Tabari as saying: يَعْنِيَانِّ بِذَلِكَ: وَاِجْعَلْنَا مُسْتَسْلِمِينَ لأَمْرِكَ، خَاضِعِينَ لِطَاعَتِكَ، لَا نُشِرْكُ مَعَكَ فِي الطَّاعَةِ أحَدًا سِواكَ، وَلَا فِي الْعِبَادَةِ غَيْرَكَ – ابن كثير في تفسير القرآن العظيم 1/ 446 By "Our Lord, make us Muslims [in submission] to you" they mean, to make us surrender to your command, submissive to your obedience and not associate anything in obedience with you nor in worship. (Ibn Kathir, Tafsir al-Qur'an al-Azeem, Vol. 1, p. 446) 3. Islam: Comprehensive and Particular One of the better classical definitions, elaborating on and differentiating between its different levels was given by Ibn Taymiyyah who explored the nature of Islam, integrating its different senses and characterising it as comprising three integrated aspects - shariah, tariqah and haqiqah: لفظ الإسلام يجمع معنيين: أحدهما الانقياد والاستسلام. والثاني: إخلاص ذلك وإفراده. كقوله: "ضرب الله مثلا رجلا فيه شركاء متشاكسون ورجلا سلما لرجل". وعنوانه قول لا إله إلا الله. وله معنيان. أحدهما: الدين المشترك وهو عبادة الله وحده لا شريك له الذي بعث به جميع الأنبياء; كما دل على اتحاد دينهم نصوص الكتاب والسنة. والثاني ما اختص به محمد من الدين والشرعة والمنهاج - وهو الشريعة والطريقة والحقيقة - وله مرتبتان: أحدهما الظاهر من القول والعمل وهي المباني الخمس. والثاني: أن يكون ذلك الظاهر مطابقا للباطن. The word Islam comprises two meanings: - The first one signifies surrender and submission, whereas - the second signifies being sincere and monotheistic in showing the first. As Allah says: "Allah presents an example: a slave owned by quarrelling partners and another belonging exclusively to one man". Its title is la ilaha ila Allah (There is no god but Allah) and it also has two meanings: - the comprehensive deen sent to all Prophets to worship Allah alone while not associating anything in worship with Him. - the second is which has been particularly sent to Muhammad (saw) in respect of the deen and Shari'ah and method. This the shari'ah (law) and tariqah (way) and haqiqah (truth). This is also subdivided into two classes: - one refers to the external words or deeds i.e. the five pillars. - the other, however, signifies the conformity between what is external and what is internal. (Majmu al-Fatawa, Vol. 1, p. 14) Analysis Most of the definitions introduced by classical Muslim scholars do not provide us with a holistic and comprehensive view of Islam that is helpful to our contemporary context. Firstly, many of these definitions were produced in the historic context of theological debates over relations between Imaan and Islam, i.e., whether they were the same or not. Those seeing them as the same defined Islam as the submission and surrender to Allah; internally or externally. Those distinguishing them defined Islam as the external submission to Allah. Secondly, some definitions neglected considering the holistic meaning of Islam as a deen, leaving such discussions to the literature discussing the dar al-Islam and dar al-Kufr paradigms. Whilst Islam is a multifaceted word that includes a wide range of meanings and senses as it may represent the purpose of our existence and Allah's eternal message to mankind to worship Him alone or it may specifically refer to the deen sent by Allah to Muhammad (saw), when used to refer to the notion of a deen, Islam refers to the collective embodiment of revelation, social arrangements in accordance with revelation, within the context of which individuals can believe and act. Conclusion Islam is a term referring to a wide range of meanings and senses. The definitions introduced by the classical scholarship, however, do not provide us with one comprehensive view of Islam that is helpful to our era. Most of these definitions revolve around the linguistic definition of the term as it means the absolute surrender and submission to Allah alone and the complete obedience to all His precepts and ordinances, while not associating anything in worship with Him, whilst territorially this means revelation must determine structures, organisations and institutions. ​​​​​​References Abu Hanifah, Al-Fiqh al-Akbar   Baghawi, Ma'lim al-Tanzil   Fayumi, Al-Misbah al-Munir Ibn Abi Ya'la, Al-I'tiqad   Ibn al-Qayyim, Tariq al-Hijratin Ibn Kathir, Tafsir al-Qur'an al-Azeem  Ibn Manzur, Lisan al-Arab Ibn Rajab, Jami al-Ulum wa al-Hikam  Ibn Taymiyyah, Majmu al-Fatawa   Jurjani, Al-Ta'rifat Taftazani, Sharh al-Aqa'id al-Nasafiyyah