Narrated Hudhayfah: The Prophet ﷺ said: Do not say: "What Allah wills and so and so wills, " but say: "What Allah wills and afterwards so and so wills.
Hadith Referenceسنن ابي داود / كتاب الأدب / 4980
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:إسناده صحيح, مشكوة المصابيح (4778)
Hadith Takhrij« تفرد بہ أبوداود، (تحفة الأشراف: 3371)، وقد أخرجہ: مسند احمد (5/384، 394، 398) (صحیح) »
Brief Explanation
1؎: Because in this phrase, the will (mashiyyah) of Allah is combined with the will of another, whereas in the phrase "if Allah wills, then so-and-so wills," there is no such issue, because after Allah's willing, there is no objection in mentioning the willing of another.
Explanation & Benefits
Shaykh Umar Farooq Saeedi
Benefits and Issues: In the first sentence, associating others in Allah’s will (mashiyyah) is implied. This is impermissible and unlawful, for only that occurs which Allah alone wills. However, in the second sentence, if the will of others is mentioned with a distinction, then it is permissible.
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 4980