The Quran repeatedly emphasizes Allah's absolute knowledge and power, which are foundational to the concept of divine decree. Allah is Ever All-Knowing, All-Wise and Allah is Knowing of that within the breasts, affirming His comprehensive awareness of all thoughts, intentions, and hidden matters. This extends to the very fabric of creation, as 6:2 to Him]. Tafsir Ibn Kathir elaborates on this, explaining that the "stated term" refers to the span of earthly life, while "another determined term" signifies the Hereafter, known only to Allah. This divine knowledge is so encompassing that not a leaf falls, but He knows it, and He knows whatever there is on the land and in the sea.

Allah's power is equally absolute, as He is the Effecter of what He intends. His command is one of ultimate authority, where when He decrees a thing, He only says to it: "Be!" and it is. This creative power is manifested in the shaping of humanity, He it is Who shapes you in the wombs as He wills. Tafsir Ibn Kathir clarifies that this includes determining gender, appearance, and destiny, emphasizing that nothing escapes His power. The Quran reinforces that 6:107, demonstrating that even human choices operate within His overarching will.

The Quran clearly states that all events, both good and challenging, occur by Allah's permission and decree. In times of conflict, such as the Battle of Uhud, believers are reminded that 3:166. Even if individuals sought to evade danger, 3:154. This truth serves to quell human anxiety and regret, as 3:156. Tafsir Ibn Kathir highlights that Allah instills such thoughts in disbelievers' hearts as a cause of regret, while simultaneously affirming that He is the one who gives life and causes death.

The span of life itself is predetermined; for every nation is a [specified term], and 7:34]. Disasters and misfortunes are likewise preordained, as 57:22. This comprehensive pre-ordination extends to the individual, as 9:51, fostering a sense of trust (tawakkul) in divine providence.

While Divine Decree is encompassing, Islam maintains the principle of human free will and accountability. The Quran states, 4:32, directly linking actions to consequences. Despite Allah's ultimate will, individuals are responsible for their choices. The concept of guidance and misguidance illustrates this delicate balance: 16:93. Tafsir Ma'arif-ul-Quran notes that Allah's guidance is absolute power, but also highlights a Hadith stating, "There is no heart which is not there in between the two of Allah's fingers - He makes it firm on the truth as long as He wills, and turns it away from the truth when He wills". This implies a dynamic interaction between divine will and human inclination.

The verse 81:29 further clarifies that human will is subordinate to Divine Will. However, this does not absolve individuals of responsibility. Instead, it underscores that human actions, whether good or evil, contribute to the outcomes ordained by Allah, as He makes them fall back for what they earned. The purpose of life is a test, where individuals are to strive and make choices. As Tafsir Ma'arif-ul-Quran explains, the adornment of worldly things is a test to see who among them acts best. This perspective encourages vigilance in one's deeds, acknowledging that one sin can lead to another, just as good deeds attract more good.

Scholars have extensively delved into the intricacies of Al-Qada' wal-Qadar, clarifying its implications. Tafsir Ibn Kathir, in discussing the story of Zakariyya (peace be upon him) being blessed with a child in old age, highlights that Allah does what He wills and nothing is beyond His power. This understanding applies not only to grand cosmic events but also to the most personal aspects of human life, affirming Allah’s comprehensive wisdom and ability. The concept of "appointed term" (ajal) is vital, with scholars like Sa'id bin Jubayr and Ibn Abbas identifying two terms: one for individual death and another for the Day of Resurrection. The precise timing of the latter is known only to Allah, emphasizing the limits of human knowledge.

The balance between divine decree and human agency is a recurring theme in scholarly commentary. When discussing the defeat at Uhud, Tafsir Ibn Kathir explains that while the disaster occurred “by the leave of Allah” and was a means “to test the believers”, it also arose from yourselves due to the archers' disobedience. This highlights that divine decree often incorporates the consequences of human choices and actions. Furthermore, Allah's promises of victory and reward for the righteous are unwavering, as none can alter the Words of Allah. This divine assurance extends to the ultimate triumph of believers, as seen in the accounts of previous prophets who endured denial and harm until Allah's help reached them.

Belief in Al-Qada' wal-Qadar has profound implications for a Muslim's practical and spiritual life. It fosters deep trust in Allah, even when faced with adversity, as believers acknowledge that 9:51. This trust encourages patience, as shown by the prophetic narratives of the Companions facing trials. The hardships faced by the Muslims at Uhud were described as a “test, not punishment”, intended to distinguish true believers from hypocrites and to purify hearts.

This belief also encourages active engagement in good deeds and striving for righteousness. Although outcomes are ultimately in Allah's hands, individuals are responsible for their efforts. The concept of taqwa (fear of Allah) is presented as a fundamental virtue, ensuring that believers spend their wealth righteously, maintain sincerity, and enjoin good while forbidding evil. As indicated in the context of spending wealth, what loss have they if they had believed in Allah and in the Last Day, and they spend out of what Allah has given them for sustenance. The verse if you avoid the great sins which you are forbidden to do, We shall remit from you your (small) sins provides an incentive for moral uprightness, clarifying that avoiding major sins is key to the remission of minor ones.

Furthermore, the Quran urges believers to actively engage in Jihad (struggle in the way of Allah), even when facing overwhelming odds, understanding that victory comes from Allah. The example of the Prophet's persistence in inviting people to Islam despite their rejection, and the call to fight even if alone, highlights the importance of sustained effort and reliance on divine support.

The doctrine of Al-Qada' wal-Qadar cultivates a unique spiritual disposition. It teaches humility, reminding believers that all blessings are from Allah, and envy for others' worldly advantages is discouraged: 4:32. Instead, one should ask Allah of his bounty. Tafsir Ma'arif-ul-Quran explains that striving to excel in good deeds is encouraged, as these are within human control and bring reward. However, coveting unacquirable qualities like beauty or lineage is deemed futile and potentially sinful.

The belief in divine decree also reinforces ethical conduct, particularly in areas like financial dealings and justice. The Quran strictly prohibits consuming others' property by false means, condemning theft, bribery, and fraudulent transactions. It also emphasizes the importance of amanah (trusts), asserting that offices of authority are divine trusts that must be entrusted to the capable and deserving. Such practices ensure a just and harmonious society, reflecting Allah’s justice and wisdom. The Quran's emphasis on justice in all dealings, even with non-Muslims, is absolute, as when you judge between people, judge with fairness.

The Prophet's Sunnah provides practical models for living this belief. His advice to "Ask Allah for your well-being" but to be patient if encountering an enemy, knowing that "Paradise is under the shade of swords" (Bukhari, Muslim), demonstrates the ideal balance of proactive effort and patient acceptance. The narrative of `Amr bin Al-`As performing Tayammum due to fear of death from cold, and the Prophet's approval, illustrates that divine commands are accompanied by mercy and ease, adapting to human limitations while upholding core principles.

In essence, Al-Qada' wal-Qadar is not an invitation to fatalism but a call to profound faith and responsible action. It reminds humanity that every breath, every event, and every outcome is part of a grand divine plan, overseen by Allah, the All-Knowing and All-Wise. This understanding instills peace in the heart of the believer, knowing that ultimate justice and mercy prevail, encouraging them to live a life of sincere worship, righteous deeds, and unwavering trust in their Creator.