Aishah said, "The Messenger of Allah ﷺ never performed the forenoon prayer, yet I perform it. The Messenger of Allah ﷺ would sometimes abandon a deed that he loved to do, fearing that people would take it up and it would then be made obligatory upon them."
حدثنا القعنبي عن مالك عن ابن شهاب عن عروة بن الزبير
أنها قالت ما سبح رسول الله ﷺ سبحة الضحى قط وإني لأسبحها وإن كان رسول الله ﷺ ليدع العمل وهو يحب أن يعمل به خشية أن يعمل به الناس فيفرض عليهم
Bukhari narrated it in the Book of Tahajjud, chapter "The Prophet's ﷺ encouragement to perform night prayers," etc., no. 1128, and Muslim in the Book of the Prayer of Travelers, chapter "The recommendation of praying Duha," etc., no. 718, from the hadith of Malik through this same chain, and it is found in the Muwatta (Yahya recension), 1/152, 153.