Binding force (luzum), fiqh and usul rulings

Luzum, in lexicon, is staying with a thing and not parting from it; to be bound by money is to owe it, and divorce binds when its ruling takes effect, which is the ending of marriage ¹. Jurists use luzum to mean obligation and necessity, and in contracts, the impossibility of rescission ^{1 2}.

The duty to keep to the community and not to rise against rulers is binding, on the hadith of Hudhayfa to keep the community and its imam. Keeping to a deed, meaning doing it constantly, is recommended for voluntary acts, on the hadith that the most loved deeds to God are the most constant, though small ^{1 3}. Al-Shatibi held that if a deed taken on with intent of constancy is beyond the usual burden or brings boredom, it is disliked from the start, since religion is easy; he cites the hadith of Abd Allah ibn Amr about fasting and night prayer ³. Ibn al-Qayyim held that no one may bind himself to a self-invented form of worship as if it were an obligation ³.

Detaining a debtor is a penalty attested in the Sunna, on the report of Kaʿb ibn Malik and Ibn Abi Hadrad, and the jurists have made it the right of the creditor. The Hanafis allow the creditor to hold his debtor day and night, following him in his standing and sitting, but not in the mosque or the sun, nor preventing him from earning ^{3 4}. The Shafi'is let the creditor ask for imprisonment instead; the Hanbalis and Malikis forbid holding a poor debtor, but permit holding a well-off one who delays, if he might flee ⁴.

Al-Tufi says that the obligatory is what is necessary and due ^{4 5}.

Obligation comes from God, who binds the servant to what He ordained, as prayer and alms when their causes and conditions are met, and to what the duty cannot be completed without; from another, as obedience to the ruler in what is not sinful, his deputies, the judge in his rulings, the husband in what is customary, the guardian over the property of his ward, and the principal over his agent ^{5 2}; or from oneself, as in a contract, the conditions that are lawful, and the one-sided words such as endowment, surety, covenant, vow, oath, emancipation, divorce and return ².

A contract is binding when neither party may rescind it without the other's consent. Sale, salam and lease are binding; marriage is binding and does not cancel by mutual consent, though some say it does. Deposit, partnership and agency are permitted, and either side may end them ². A contract may be binding for one side and permitted for the other, as a pledge for the pledgee, who alone may end it ⁶. A binding contract may become permitted by option or defect; a permitted contract may become binding, as agency once the agent's right attaches ⁶. The Shafi'is and Hanbalis grant the option of the session, so a sale is permitted until the parties part ⁶. Gift is disputed: binding by agreement for Malik, binding on receipt with the donor's leave for al-Shafi'i and Ahmad, and revocable after receipt for Abu Hanifa ⁶.

For the Hanafis a corrupt contract is formed but not binding, since it is liable to be rescinded for God's right; it may bind if the defect is removed ^{6 7}. A promise is generally not binding, though some say it binds in conscience but not in law; for the Malikis there are four views, the soundest that it binds if it has a cause and the promisee acted on it ⁷.

In usul, binding is that one matter is fixed when another is fixed, as the effect is bound to its cause; calling the bound by its binder is a figure of speech, and the sense a text implies beyond its aim is called in the Hanafi school the indication of the text, as the period of pregnancy is inferred from two verses ^{7 8}. Does a judge's ruling bind what it implies? The Hanbalis say yes, so that another judge may not rule against it ⁸.