Evidence for belief in Qadar1 can be found in the following statements of Allah, the Most High:
“Allah’s command is a determined decree.”
[Surah al-Ahzab, 33:38]2
1Qadar, coming from the root word qadara (evaluate), may be defined as Allah’s predestination of everything for His creation in accordance with His prior knowledge (Believing in Qadar, p.8); it is Allah’s decree or decision as in the verse.
2This verse concerns the incident of the Prophet’s adopted son, Zayd ibn al-Harithah’s divorce from the Prophet’s cousin, Zaynab, and the Prophet’s subsequent marriage to her. The Prophet (peace be upon him) tried to avoid and hide Zayd’s marital problems from the community, however it occurred.
“Allah’s command in a determined decree,” means that Allah’s command which He has decreed must be inevitably come to pass; nothing can prevent it or avert it, for whatever He wills happens, and whatever He does not decree, does not happen. (Tafsir Ibn Kathir, vol. 7, p. 699).
“Indeed, I have created all things according to predestined proportions [Qadar].”
[Surah al-Qamar; 54:49]
Also derived from the same root is the word Qadr (amount) from which Laylatul-Qadr (the night in which Allah sends down His annual decree ad decides the amounts of all things relating to his creation) comes. It is synonymous to Qadar in this context. The Divine Names al-Qaadir (Most Able), al-Qadeer (All-Powerful) and al-Muqtadir (Omnipotent) are all derived from the root.
Qadaa (decision) is the implementation of Allah’s decree (Al-Mufradaat, p. 406) as in the verse.
“When He decrees a matter, He only says to it: ‘Be!’ – and it is.”
[Surah al-Baqarah, 2:117]
Some scholars like Ibn hajar al-‘Asqalaanee held the opposite view. He said, ‘The scholars say that Qadaa is the general decree from eternity, and Qadar refers to the details of that decree and how they are implemented.”(Fat’hul baaree, vol. II, p. 477 & 149). The overwhelmingly accepted position makes Qadaa the universal. General eternal decree, and Qadar the individual development or application of that in time. (The Encyclopedia of Islam, p. 199).
When the terms Qadar and Qada‘ are mentioned separately they are synonymous but when mentioned together, Qadar means the predestination and when what is predestined occurs it is called Qada’. (Majmoo’ al-Fataawaa, vol. 2, pp. 79-80).
In-hope-and-faith 