Rukn
Rukn names a part so essential to an act or contract that without it, nothing recognizable as that act exists at all.
What it means for me: Rukn tells you a piece is load-bearing. Remove it, and there is no flawed version of the act left standing; there is no act at all.
Example: A scholar explains a sale's two pillars: an offer and an acceptance. Without either one, no contract exists at all, not merely an imperfect one. The rest of the deal's details would not matter yet.
Do not confuse with: Shart, condition. A rukn is part of the act's own makeup. A shart stands outside it, required for the act to count but not one of its parts.
If scholars differ: The majority define rukn as anything belonging to an act's essential makeup. In contract law, the Hanafi school narrows rukn to the offer and acceptance alone, treating other elements as conditions instead.
See the term in context
What is the difference between a pillar (rukn) and an obligation (wajib) in prayer?
First, the difference between a pillar (rukn) and an obligation (wajib) in prayer is that a pillar is not waived whether intentionally, by oversight, or out of ignorance; rather, it must be performed. As for an…
What is the difference between a pillar (rukn) and an obligation (wajib) in prayer, and when are the transitionary takbirs and the tasmi' (saying "Sami'a Allahu liman hamidah") uttered?
The questioner did not specify the paragraph that was unclear to him. However, if he meant the sum of what was mentioned before his question, then these are the duties of prayer. The difference between a pillar (rukn)…
Does the prostration of forgetfulness (sujud al-sahw) become void for the worshipper (ma'mum) if it entails abandoning a pillar (rukn) or an obligatory act (fard), on the basis that the imam is responsible?
The Imam does not bear responsibility for a follower's (ma'mum's) forgetfulness in omitting a pillar (rukn) of prayer, such as prostration (sujud), bowing (ruku'), or sitting (julus). Rather, the follower must perform…
Questions that use it
Is it mentioned in the Qur'an or Sunnah that supplication at the Yemeni Corner (Rukn al-Yamani) is answered, and is that specific to the time of Hajj and Umrah or does it include all other times?
What is the difference between a condition (shart), a pillar (rukn), and a duty (wajib)?
Should one perform the prostration of forgetfulness (sujud al-sahw) if they accidentally omitted a pillar (rukn) while leading a congregational prayer?