The Definition of “Iman”
Sh. `Ata’ Ibn Khalil (Allah preserve him)
“It is necessary to pause here and discuss the topic of the difference between ahkam shar`iyya and iman and the differences between them. I say and with Allah is all tawfiq:
Iman is related to tasdiq al-jazim (‘decisive assent and belief’) whereas ahkam al-shar`iyya is related to performing and carrying out actions. So, iman is defined as tasdiq al-jazim al-mutabiq li’ l-waqi` `an dalil (‘a decisive belief that conforms with reality based on evidence’).
فالإيمان هو التصديق الجازم المطابق للواقع عن دليل…
The meaning of tasdiq al-jazim means to have utter conviction (qana`a qati`a) that has no doubt whatsoever. This is also the linguistic meaning of iman which is tasdiq al-jazim. The meaning of mutabiq li ’l-waqi` is that the sensed reality corroborates the belief and does not contradict it. Both elements of iman, i.e. tasdiq al-jazim and mutabi li ’l-waqi` require definitive evidences (dalil maqtu`) to establish its validity which can be either:
عقليا أي نتيجة البحث العقلي في الوقائع المحسوسة … أم نقليا أي عن طريق النقل المقطوع به عن الله سبحانه في كتابه الكربم أو عن رسوله في حديثه المتواتر عنه…
 Rational (`aqliyyan): these are conclusions from the rational investigation of the sensed reality such as the study of created things leads to the existence of a Creator – Allah (swt) – or the study of the words of Allah – the Noble Qur’an – leads to the conclusion that it is not the words of any human being but the word of Allah (swt) or that Muhammad (saw) who brought the words of Allah is indeed the Messenger of Allah.
 Textual (naqliyyan): which is a definitive transmission channel from Allah in the form of His Noble Book (swt) or from the Messenger of Allah (saw) in the form of hadith mutawatir such as belief in the matters of the unseen, Angels, the previously revealed Scriptures, the previous Prophets, the Hereafter and the Qadar – its good and bad…”
- Shaykh `Ata’ then concludes the section stating:
“Iman with the definition we have just given (‘a decisive belief that conforms with reality based on evidence’) neither increase nor decreases because it is a decisive conviction and definitive conviction or assent cannot be anything but complete, i.e. it cannot be 90%, that then increases to 95% and then 100% only to decrease to 95% or 90% because deficiency or decrease means lack of decisiveness which is doubt and if this is the case then that would entail disbelief (kufr)…”
And with Allah is all success.