Scholars agree that every action actually has its unique ruling. Killing an innocent person and telling a small innocent lie are both forbidden (haram); but one is much more serious than the other. All actions done by morally responsible individuals can receive one of eight rulings.
1) Fard (obligatory) is a definite order, proven by a decisive text[I] that has a fixed meaning not open to other possible interpretation. One is bound to believe in and act upon the obligatory. One who denies it can easily fall outside the fold of Islam, and one who does not act upon it is sinful.
2) Wajib (necessary) is a definite order, proven by a text open to possible interpretation. Denying something that is wajib is moral corruption (fisq), but not disbelief. It is sinful to omit it.
Omission of wajib parts of salah (ritual prayer) will not invalidate it, but it becomes necessary to repeat the prayer if it was done intentionally. If it was done due to forgetfulness, sajdah sahw is necessary (wajib).
3) Sunnah mu’akkadah (emphasized sunnah) is what the Prophet (peace be upon him) or sahaba (companions of the Prophet) did most of the time (and was not a worldly habit). One who omits it without excuse deserves criticism, not punishment. However, habitually omitting it is sinful because it implies ‘turning away’ from the guidance of the Prophet (peace be upon him), which we have been ordered to follow.
4) Mustahabb (recommended) is what the Prophet (peace be upon him) did occasionally. One who performs it is rewarded, and it is not blameworthy to omit it.
5) Mubah (permissible) is that which involves neither reward nor punishment. However, such actions are rewarded if done with good intention.[II]
6) Makruh tanzihan (slightly disliked) is what we have been lightly ordered to abstain from, but it is not sinful or blameworthy to do it. There is reward in abstaining from it.
7) Makruh tahriman (prohibitively disliked) is what we have been definitely ordered to abstain from, proven by a text open to other possible interpretation. Denying such a thing would imply misguidance, but not disbelief. Performing such an action is sinful.
8) Haram (forbidden) is what we have been definitely ordered to abstain from, proven by a decisive text.
What is fard and wajib must be performed. What is makruh tahriman and haram must be abstained from. It is strongly emphasized to perform sunnah mu’akkadah, and blameworthy to omit them without reason. Mustahabb should be performed, and makruh tanzihan should be avoided. The permissible should be followed by good intentions for reward, and one should avoid wastefulness.
The way of love and servitude involves doing everything the Lord has ordered, whether definitely or lightly, and avoiding everything the Lord has forbidden, whether definitely or lightly. However, the best way to do this is gradually and steadily.[III]
[I] A decisive text is the entire Quran and those hadiths that have multiple connected chains of narration [mutawatir].
[II] Wasting the permissible is blameworthy and can even become sinful if it is excessive.
[III] Abu Hurayra (Allah be pleased with him) related that the Messenger of Allah (Allah bless him and give him peace) said, “Verily, this religion is easy, and no one makes their religion excessively difficult except that it overcomes them. So be moderate, do your best, and be of glad tidings…” [Bukhari (39), Muslim (2816)]
© Shaykh Faraz Rabbani, SunniPath, translated with permission by M. Amin.
Source: The Absolute Essentials of Islam, Fall 2004.