At the heart of Islam lies the principle of absolute submission (Islam) to the One God (Allah), coupled with unwavering monotheism (Tawhid). This fundamental belief is articulated in numerous Quranic verses, such as the declaration that 21:108]. This call to monotheism is not unique to the final Prophet Muhammad ﷺ, but has been the consistent message of all prophets, as affirmed by Allah: And We did not send any Messenger before you (O Muhammad) but We revealed to him (saying): La ilaha illa Ana none has the right to be worshipped but I (Allah), so worship Me (alone and none else), as explained by Ibn Kathir.

The act of "submitting one's face to Allah" signifies total dedication, both in belief and action, performed with sincerity, as explicated by Ibn Kathir. This sincerity (ikhlas) is paramount; deeds must be performed solely for Allah's sake and in conformity with the divinely revealed law (Shari'ah). Ibn Kathir explains that a deed performed sincerely but not in accordance with the Shari'ah will be rejected, just as a deed conforming outwardly to the Shari'ah but lacking sincerity will also be rejected. This dual requirement ensures that Islam is both an inward spiritual state and an outward manifestation of obedience. The Prophet Muhammad ﷺ underscored this by stating, "Whoever performs a deed that does not conform with our matter (religion), then it will be rejected" (Muslim).

The universal nature of this submission is highlighted by the verse stating that all beings in the heavens and earth submit to Allah, whether willingly or unwillingly. Tafsir Ibn Kathir explains that faithful believers submit in both heart and body, while disbelievers, though not submitting willingly, are still subject to Allah's irresistible power and control. Mujahid clarifies that this unwilling submission refers to Allah's covenant with all creation. This points to a natural, cosmic Islam, transcending human conscious choice, which humanity is then invited to embrace consciously.

While submission (Islam) fundamentally means affirming the Oneness of Allah and following His prophets, its practical manifestation is encapsulated in core tenets. The Prophet Muhammad ﷺ elucidated the foundation of Islam: "Islam is based on (the following) five (principles): 1. To testify that none has the right to be worshipped but Allah and Muhammad is Allah's Messenger (ﷺ). 2. To offer the (compulsory congregational) prayers dutifully and perfectly. 3. To pay Zakat (i.e. obligatory charity). 4. To perform Hajj. (i.e. Pilgrimage to Mecca) 5. To observe fast during the month of Ramadan" Sahih al-Bukhari 2:1. These pillars provide the structural framework for a Muslim's life, operationalizing the principle of submission.

The significance of these practices is underscored by the reward promised for sincere adherence. The Quran declares that 2:112. Abu Huraira narrated that the Prophet ﷺ stated, "If a person embraces Islam sincerely, then Allah shall forgive all his past sins, and after that starts the settlement of accounts, the reward of his good deeds will be ten times to seven hundred times for each good deed and one evil deed will be recorded as it is unless Allah forgives it" Sahih al-Bukhari 2:34. This demonstrates the immense divine mercy associated with embracing Islam and striving for righteousness. The companion Talha bin 'Ubaidullah related an encounter where a man inquired about the essentials of Islam – prayers, fasting, and zakat – and upon being told there was no more obligatory, declared he would neither do less nor more. The Prophet ﷺ remarked, "If what he said is true, then he will be successful (i.e. he will be granted Paradise)" Sahih al-Bukhari 2:39. This highlights that fulfilling the core obligations of Islam is sufficient for salvation.

Beyond these fundamental acts of worship, Islam also encompasses ethical conduct. When asked about the best deeds in Islam, the Prophet ﷺ replied, "To feed (the poor) and greet those whom you know and those whom you don't know" Sahih al-Bukhari 2:21. This emphasizes the social dimension of Islam, promoting compassion, generosity, and community cohesion.

The Quran asserts the exclusivity of Islam as the acceptable religion to Allah: 3:85. Ma'arif-ul-Quran elaborates that "Islam" here refers specifically to the final Shari'ah revealed through Prophet Muhammad ﷺ, which abrogated all previous divine laws. While past prophets and their communities were considered "Muslim" in the general sense of submitting to Allah's will for their specific time and place, after the advent of Prophet Muhammad ﷺ, his teachings represent the ultimate and universal form of Islam until the Day of Judgment. This explains the Prophetic statement, "Had Musa been living this day, following me would have been incumbent upon him too."

However, Islam also acknowledges a broader principle of submission that spans across prophetic traditions. The Quran recounts how the disciples of Jesus declared, 5:111]. Ibn Kathir explains that "Awhaytu" (inspired) in this context means Allah put belief in their hearts, leading them to declare their submission. This demonstrates that the core principle of submission to God and His messengers has been a continuous thread throughout divine revelations. Ma'arif-ul-Quran explains that the essence of religion, whether Islam, Christianity, or Judaism, lies in obeying Allah in belief and action, with sincerity, and in accordance with the specific Shari'ah appointed through His prophets. Since the revelation of the Quran, this means accepting and following the Islamic Shari'ah of Prophet Muhammad ﷺ.

The Quran issues stern warnings against rejecting Islam and engaging in hypocrisy. For those who disbelieve, the consequence is severe, as they will be among the losers in the Hereafter. This is a theme echoed in the descriptions of those whose hearts are sealed or rusted due to their disbelief and sins. Tafsir al-Jalalayn states that Allah has set a seal on the hearts of disbelievers, preventing good from entering, and a covering on their eyes so they do not see the truth. Ibn Kathir explains this sealing as a consequence of sins accumulating in the heart, ultimately leading to a state where one can no longer distinguish good from evil, referencing the concept of "Ran" (rust) mentioned in. This is further supported by a Hadith from Abu Hurayrah: "When the believer commits a sin, a black dot will be engraved on his heart. If he repents, refrains and regrets, his heart will be polished again. If he commits more errors, the dots will increase until they cover his heart. This is the Ran (stain) that Allah described, Nay! But on their hearts is the Ran (stain) which they used to earn" (Tirmidhi, Hasan Sahih).

Hypocrisy, the outward display of belief while concealing disbelief, is particularly condemned. The Quran describes hypocrites as those who, when they meet those who believe they say, ‘We believe’; but when they go apart away from them and return to their devils their leaders they say ‘We are with you in religion; we were only mocking them the believers by feigning belief.. Ibn Kathir explains that these individuals aim to deceive believers and gain benefits, but ultimately, they deceive none but themselves, as Allah knows their inner reality. The punishment for such deceit is severe, as Allah "mocks at them and leaves them increasing in their deviation to wander blindly", meaning He gives them respite only to increase their sinfulness. Ma'arif-ul-Quran highlights that the hypocrites mentioned in the Quran, despite offering prayers like Muslims, were not considered true Muslims because they did not have faith in all the essentials of Islam as believed by the Companions. This distinction clarifies that mere outward observance without inner conviction and full acceptance of Islamic doctrines is insufficient.

The path of Islam requires steadfastness (istiqamah) and adherence to divine commands without deviation. Prophet Muhammad ﷺ and his followers are enjoined to “stand firm - as you have been commanded - you, and those who have repented [ from kufr and are ” with you, and do not cross the limits]. Tafsir al-Jalalayn defines steadfastness as maintaining obedience to God and staying away from disobedience. Ma'arif-ul-Quran further elaborates that istiqamah is a comprehensive concept covering all aspects of a Muslim's life – beliefs, acts of worship, transactions, and morals – urging adherence to the straight path without any tilt, decrease, or excess. The Prophet Muhammad ﷺ himself felt the weight of this command, saying that Surah Hud, which contains this verse, had made him old, signifying the immense challenge of perfect adherence.

The Quran also highlights the divine purpose behind creation: that He might try you, which of you is the best in deeds. Ibn Kathir clarifies that "best in deeds" implies sincerity for Allah alone and conformity to the Shari'ah, rather than merely the quantity of deeds. This emphasis on quality and sincerity is what defines true ihsan (perfection), as explained by Ma'arif-ul-Quran.

The blessings for those who remain steadfast are immense. Not only will they have their reward with their Lord, free from fear and grief, but Allah promises triumph to those who believe and support His cause. The Quran refers to the Christians who recognized the truth and embraced Islam upon hearing the Messenger's revelation, their eyes overflowing with tears, saying, Our Lord, we believe, so inscribe us among the witnesses. For this, Allah rewarded them with Gardens under which rivers flow, abiding therein forever. This demonstrates Allah's mercy and justice in rewarding sincerity and adherence to truth, regardless of prior affiliations, once the final message of Islam is presented.

Islam, as a comprehensive way of life, profoundly encompasses peace, surrender, and conscious submission to Allah. This multifaceted framework, rooted in divine revelation and prophetic guidance, establishes monotheism, outlines essential practices, and defines the criteria for salvation. While unequivocally affirming its unique status as the final and universal religion, Islam simultaneously recognizes the historical continuity of divine guidance and the intrinsic human inclination towards truth. The Quran and Hadith, clarified by scholarly interpretation, illuminate the path for believers to achieve both worldly prosperity and ultimate success in the Hereafter through sincere obedience and steadfastness to Allah's commands.