Both parties in a business transaction have the right to annul it so long as they have not separated; except in transactions which have been made subject to the right of parties to annul them.
The Book of Transactions - Sahih Muslim 1531a
Narrated by Hakim bin Hizam: The Prophet (ﷺ) said, "Both the buyer and the seller have the option of canceling or confirming the bargain unless they separate."
Commentary on the Option Period (Khiyar al-Majlis)
This hadith establishes the fundamental principle of "Khiyar al-Majlis" (option of session) in Islamic commercial law. The "session" refers to the period when both parties are physically present together at the place of transaction before their separation.
The wisdom behind this ruling is to protect both parties from haste and potential regret, allowing them to reconsider the terms while all details are fresh. This option exists even if not explicitly stated in the contract, as it is an inherent right granted by the Shariah.
Conditions and Application
Separation is understood by most scholars as physical departure from the place of transaction, though some schools include verbal separation. The option remains valid until either party explicitly confirms the transaction or they physically separate.
This general rule applies to most sales contracts unless specific conditions are stipulated that override this default option, such as "Khiyar al-Shart" (stipulated option) where parties agree to extend the cancellation period beyond the session.
Legal Implications
During this option period, neither party is bound by the contract and may retract without requiring a specific reason. This protects against coercion, misunderstanding, or discovery of hidden defects immediately after agreement.
The Hanafi school holds that this option applies only to sales involving immediate exchange, while the majority of scholars apply it to all sales contracts. All agree that once separation occurs, the contract becomes binding unless other valid options remain.