The Book of the Prohibited actions

Riyad as-Salihin · Chapter 333

Abomination of saying: "What Allah Wills and so-and-so Wills"

باب كراهة قول‏:‏ ما شاء الله وشاء فلان

This short chapter guards how we speak about Allah's will alongside the will of people. The objection is to the little word 'and', which in Arabic places two things side by side as equals. To say 'What Allah wills and so-and-so wills' quietly levels the Creator with a creature, as if their wills stood on the same footing.

The remedy is a single word: 'then' (in Arabic, thumma), which signals sequence and subordination rather than partnership. Notice how a matter of grammar is really a matter of tawhid, keeping Allah's will first and supreme and every human will dependent on it and coming only after.

Hadith 1745

Hudhaifah bin Yaman (May Allah be pleased with him) said:

عن حذيفة بن اليمان رضي الله عنه عن النبي صلى الله عليه وسلم قال‏:‏ ‏ "‏لا تقولوا‏:‏ ما شاء الله وشاء فلان، ولكن قولوا‏:‏ ما شاء الله، ثم شاء فلان‏" ‏‏.‏ رواه أبو داود بإسناد صحيح

The Prophet (ﷺ) said, "Say not: 'What Allah wills and so-and-so wills', but say: 'What Allah wills, and then what so-and-so wills."' [Abu Dawud with authentic Isnad].

In plain words

Do not say 'what Allah wills and so-and-so wills,' which places them as equals; say 'what Allah wills, and then what so-and-so wills.' A small change in wording keeps Allah's will first and supreme.

Reference : Riyad as-Salihin 1745 In-book reference : Book 17, Hadith 235